Sound baffling material and device

ABSTRACT

A sound or thermal baffling device comprising an enclosure containing a variable density fluid and a force generating means for preserving and creating the structure and form of the enclosure, the shape and composition of the enclosure crafted to vary the baffling characteristics of the enclosure, and a further embodiment showing how a cellular material containing a variable density fluid may be created and used, and a still further embodiment showing improvements to ear protectors and head phone sets, including latching means for attaching these and other devices to the ears and head. Various applications involving previous as well as new uses are set out, including a description of how dynamic sound baffling may be implemented.

This is a division of application Ser. No. 11/265,408 which is acontinuation in part of application Ser. No. 09/464,160, which was adivision of application Ser. No. 08/613,685 that was issued as U.S. Pat.No. 6,091,825, and the disclosure of the application Ser. No. 09/464,160is accordingly incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

This invention relates to the field of sound baffling devices, and moreparticularly the use of an enclosure containing a vacuum to bafflesound, as well as the various practical uses to which this invention maybe put. Some other improvements, which aid the invention in operation,are also shown.

Many previous sound-baffling devices also may have had no facility fordynamically adjusting the ambient sound. If such facility was present,it may have involved a change in the spatial disposition of the soundbaffling devices. The ability to dynamically alter the inherent soundbaffling characteristics of sound baffling devices may not have beenshown previously.

SUMMARY OF THE INVENTION

Although the theory of operation and/or functioning of the invention isnot fully understood, according to one of its aspects the inventioncomprises the use of an enclosure containing a vacuum to baffle sound.Although the invention may baffle sound by means of sound deflection,sound reflection, and sound absorption like some previous devices, theuse of a vacuum improves on this. A vacuum, being substantially opaqueto sound, should function as a total barrier to sound, althoughperipheral transmission and absorption along the enclosure may stilltake place.

Since a perfect vacuum should be opaque to sound, a perfect vacuumshould function as a complete barrier to sound. In practice, the vacuummay not always be perfect. Hence there may be a small amount oftransmission through the vacuum. However, this amount should be so smallas to be negligible.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the first process of manufacture that uses a materialhaving a porous structure to create a cellular material.

FIG. 2 shows the second process of manufacture that uses a pourableproduct to create a composite cellular material.

FIG. 3 shows the drawing of the preferred embodiment of the parentapplication. It illustrates how a large scale arrangement of enclosuresmay be combined to comprise a sound baffling device and how this soundbaffling device may be used in conjunction with a controlling meanshaving a controlling program and a microprocessor. The sound bafflingdevice shown in this drawing should be capable of dynamicallycontrolling the ambient sound.

FIG. 4 shows how the single path connecting means may be passed throughthe tubular tunnel within a hollow tubular fitting means.

FIG. 5 shows how the single path connecting means may be carried withinthe grooves of a fitting means comprised of arc shaped bands.

FIG. 6 shows the lip contour that may be applied to the lips of soundbaffling cups and the medial side of some of the latching means.

FIG. 7 shows how the lip contour fits the human body surface in theregion of the head and neck.

FIG. 8 shows the combination of sound baffling cups having a lip contourwith headphone sets.

FIG. 9 shows an improved connecting means for headphone sets with soundbaffling cups. The improvement combines the two branches of theconnecting means, which previously depended from the sound baffling cupsinto one branch.

FIG. 10 is a separate view of the jointed clip. It shows the jointedclip in an opened position so as to give a better view of the groovesand tongues etc.

FIG. 11 shows the drawing of the preferred embodiment of the instantapplication. It illustrates how a large scale arrangement of enclosuresmay be combined to comprise an sound baffling device and how this soundbaffling device may be used in conjunction with a controlling meanshaving a controlling program, a microprocessor, and a neural net. Alsoit shows a pressure varying means, which contains a means for admittingand removing and is capable of admitting and removing fluids havingdifferent densities and acoustic impedances to and from the enclosure.This is further facilitated through the application of a vacuumcapacitor. The sound-baffling device shown in this drawing should becapable of dynamically controlling the ambient sound.

FIG. 12 shows one basic flowchart that comprises the description of alogic flow that may be used to organize the means for correlating, thepressure varying means (which includes the means for admitting andremoving), a computer, and a neural net, to function in a logical andoperational manner.

FIG. 13 shows a noise canceling transduction circuit.

FIG. 14 shows a sound canceling transduction circuit.

FIG. 15 shows a modulation transduction circuit.

FIG. 16 shows a modulated noise canceling transduction circuit.

FIG. 17 shows a modulated sound canceling transduction circuit.

FIG. 18 shows a shows a nodal chip assembly; the nodal chip is used todemultiplex a signal from the controlling means to select nodes foractuation.

FIG. 19 shows a flexible enclosure wall having a matrix of conductiveplates affixed thereto.

FIG. 20 depicts a flexibly walled enclosure supported by a power supplycasing or stand.

FIG. 21 depicts a charged plate assembly connected to a switch and ahigh voltage power supply.

FIG. 22 shows a pneumatic or hydraulic clip, depending on whether theactuating fluid is a liquid or a gas.

FIG. 23 is a section of FIG. 22, and most auspiciously, shows a crosssection of the expandable annular tube.

FIG. 24 shows a flat sliding clip.

FIG. 25 is a cross section of FIG. 24.

FIG. 26 is an enlarged section of FIG. 24 and, in particular shows oneexample of a holding means that may be used to connect the first and thesecond arc shaped flanges.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Although the theory of operation and/or functioning of the invention isnot fully understood, as shown in FIG. 1 according to one of its aspectsthe invention comprises a sound baffling device having at least oneenclosure (52) containing a vacuum (56), such that the transmission ofsound through said sound baffling device is substantially barred by saidvacuum.

The cutaway view of FIG. 2 expands on this. A cross section of the wallsof the enclosure is shown as well as a glimpse of the interior. Inoperation, the vacuum is contained and preserved by the walls (54) ofthe enclosure. Initially the vacuum may be created by removing matterwithin the enclosure by means of a valve (FIG. 13) located in orattached to the walls of the enclosure. This procedure should be usedwhen the enclosure is constructed for connection to a controlling means.It may allow not only the removal of the matter from within theenclosure but also allows the matter to be returned to the enclosureshould this be desired, as may often be the case where a controllingmeans is connected to the enclosure. In most cases the matter will be agas or air, or a mixture of gases. However it may sometimes bepreferable to use a liquid or particulate or granular forms of matter toachieve specialized sound baffling characteristics.

Alternatively, the vacuum may be created within the enclosure byconstructing and sealing an enclosure within a vacuum chamber. Thisassures that the vacuum within the enclosure will be maintained underambient conditions. This type of construction maintains substantiallyconstant sound baffling characteristics for the enclosure and ispreferable when these types of characteristics are required. The methodof construction may be substantially the same as that used for thecreation of vacuum chambers and vacuum bottles or containers bypreviously used engineering methods such as pinch-off (A pipe or tube isconnected to the enclosures and used as a conduit for creating thevacuum. Usually the pipe or tube is comprised of the same material asthe enclosure. After the required pressure is reached within theenclosure, the pipe or tube is pinched off sealing the enclosure (Thismay be done by using special pinch-off pliers). Heat or a sealant mayalso be applied to seal the remnant pinched off section of theenclosure. Finally the excess section of the pipe or tube is removed,leaving a sealed enclosure). Or the enclosure may be constructed withinthe vacuum chamber by taking preformed walls or sides and joining them,preferably with interlocking joints, to comprise the enclosure. Asuitable sealant is then applied to seal the joints so that the vacuummay be preserved against ambient matter. Such a sealant would preferablybe a silicone or epoxy sealant.

A still further procedure may use a hollow stem attached to a sealingsaddle or cup to remove the homogeneous fluid from the enclosure. Theenclosure is created under atmospheric pressure. Then, a hole is createdin the enclosure by using a drill, laser, or any other convenient toolhaving the requisite capacity. Next the enclosure is held fixedly withina vise or equivalent holding instrument while the sealing saddle or cupis hermetically attached above the hole in the enclosure. The hollowstem of the sealing saddle or cup is attached directly or indirectly toa vacuum pump, and the homogeneous fluid is removed from the enclosureuntil the desired internal pressure is achieved within the enclosure.

The sealing saddle or cup may also contain a tool for closing the holein the enclosure. This could be a welding tool, for metal or glassenclosures, or a sealing tool that applies a sealant to the hole, forglass or plastic enclosures, or any other tool that has the capacity tohermetically seal the rarefied homogeneous fluid within the enclosure.After the enclosure is sealed the sealing saddle should be removed fromthe enclosure prior to preparing a new enclosure.

The sealing saddle or cup may also contain a fluid transfer connectionto a matter density reservoir. In this case, after substantially allfluid is removed from the enclosure, a preferred fluid from the matterdensity reservoir may be admitted to the enclosure prior to sealing.Such a preferred fluid may be any one of the noble gases, or any otherfluid that lends novel results to the finished enclosure (e.g. the noblegases).

The advantage of this cellular material is that is allows theconstruction of a large sound baffling device that should require nointernal supporting struts for the enclosures. Because of the externalpressure that may act on the enclosure, for large enclosures internalsupporting struts may be required. This requirement may depend on thestrength and shape of the material of the enclosure as well as on theexternal pressure. However for a sufficiently small enclosure theinherent strength (the ability to resist external pressure) of theenclosures may show an increase proportional to the decrease in size,and the enclosures may therefore be able to resist the external pressureand maintain structural integrity without supporting struts.

Many materials may show this proportional increase in inherent strengthwith decreasing scale, among them the glasses and the plastics. It maytherefore be preferable that the cellular material is formed fromenclosures comprised of glass so that said material is a glass having acellular structure. A way of constructing such a material may be foundby placing a form filled with glass ellipsoids or other regular solids(e.g. a regular polyhedron), containing a vacuum inside a vacuum chamberthat is evacuated. The ellipsoids or other regular solids mayconceivably be any size attainable by existing art but it may bepreferable that the size falls into a range of proportions varying fromabout one quarter inch to about four to five inches. And anotherpreferable range of proportions may vary from about one inch to aboutfive to six inches. Heat is then applied causing the walls of the glassellipsoid other regular geometric shapes to coalesce through partialmelting, thereby forming common walls. In this way, upon cooling acellular material comprised of glass and containing a vacuum may becreated.

The same procedure may be applied to plastic globules or other regulargeometric shapes containing a vacuum. Depending on the plastic used andthe process desired, heat or a catalyst or an adhesive sealant may beapplied to the plastic globules or other regular geometric shapes. Thismay cause the walls or boundaries of the plastic globules or otherregular geometric shapes to coalesce through partial melting or bonding,thereby forming common walls. In this fashion a cellular materialcomprised of plastic and containing a vacuum may be created.

In general, when using simple ellipsoids or other regular geometricsolid shapes (e.g. a regular polyhedron), the resultant material may bemore effective when the ellipsoids or other regular geometric solidshapes are all the same size, or when their sizes fall into ageometrical progression that maximizes the filling capacity of theellipsoids or other regular geometric shapes (Filling capacity isdefined as the percentage of total material volume that is occupied bythe ellipsoids or other regular geometric shapes after random mixing forsome assemblage of the ellipsoids or other regular geometric shapes.) Ithas been found that for spheres that are of substantially the same sizeand shape the maximum filling capacity under random mixing is about0.6400 or 64%.

One of the preferable features when creating a cellular material whereinsubstantially each cell contains a vacuum, is to use a packing thatachieves the maximum amount of vacuum per volume possible. To this endan enclosure having an ellipsoid surface is capable of achieving evenbetter results than an enclosure having a spherical surface. Forellipsoids the maximum filling capacity under random mixing is higherthan what is attainable by using spheres; ellipsoids can achieve about0.6800 or 68%. Therefore another aspect of the invention comprisesreplacing the use of spherical enclosures in these embodiments of theinvention with the use of ellipsoid enclosures all having substantiallythe same size, or falling into a geometrical progression that maximizesthe filling capacity of the ellipsoids or other regular geometricshapes.

It has also been found that a preferable geometrical relationship amongspheres, ellipsoids, and other regular geometric shapes (e.g. a regularoctahedron) may be created by using two sizes proportioned in a rationof one to four; one of the smaller sized regular geometric solid shapes(e.g. a sphere or ellipsoid) to four of the larger sized geometric solidshapes. Assuming the size of the larger size regular solid to have avalue of 1, the smaller size regular solid would then fall into a rangefrom about 0.115 to 0.225, or preferably from 0.13 to 0.21, or morepreferably from 0.15 to 0.19, proportionally. (e.g. If a sphere having adiameter of 1 inch is used for the larger size, then the smaller sizewill have a diameter falling between 0.115 to 0.225 inches, orpreferably from 0.13 to 0.21 inches, or more preferably from 0.15 to0.19 inches, proportionally. The appropriate proportion of largerspheres to smaller spheres would then call for the use of four largespheres for every small sphere used. Also, from a different perspective,given an ellipsoid having a volume of 1 cubic inch, where the ellipsoidis the lesser sized regular solid, the volume of the larger sizedellipsoid would be about 5.88 cubic inches)

It may therefore be preferable that according to one of its aspects theinvention further comprises; A process of manufacture for creating acellular material containing a vacuum for baffling sound,

the first step in the process of manufacture comprising the creation ofsaid vacuum within a plurality of disjointed enclosures having anellipsoid surface,

the second step in the process of manufacture comprising the creation ofa binding mixture by mixing a binding agent with said plurality ofdisjointed enclosures containing said vacuum, the solidification of saidbinding mixture causing said plurality of disjointed enclosures tocomprise a plurality of cells containing said vacuum,

so that after completing the process of manufacture, said plurality ofcells comprises said cellular material containing said vacuum.

A further way in which a cellular plastic may be created is by mixing amolten thermoplastic material with a gas or liquid which is volatile atnormal atmospheric pressure and subjecting the mixture to elevatedtemperature or pressure in a closed chamber. The material is thenreleased from the closed chamber through a suitable die opening, therebyreleasing the pressure and causing the gas to expand. This results in apermanent porous or cellular plastic upon cooling.

If in addition thereto, the improvement comprises that the die openingis connected to a vacuum chamber, then when the vacuum chamber isevacuated concurrently with the expansion of the thermoplastic material,a vacuum may be incorporated into the cells of the material. This vacuummay be preserved against the action of ambient matter by incorporating abitumen or other sealing agent into the thermoplastic material. Or thevacuum may be preserved by applying a suitable sealant to finished unitsof said thermoplastic material before removal from the vacuum chamber.For expandable polystyrene or polyurethane such a sealant may be aurethane or epoxy sealant. And this material may be used as a bindingagent. A vacuum chamber may be filled with enclosures containing avacuum. The vacuum chamber further has the die opening above and as thecellular plastic is expanded into the vacuum chamber through said dieopening it should fill the voids between the enclosures. Uponsolidifying the cellular plastic will therefore function as a bindingagent for the enclosures containing a vacuum.

A first process by which a material having a cellular structure can becreated is shown in the sequential views of FIG. 5 which illustratesthat the invention comprises a first process of manufacture that uses amaterial having a porous structure to create the material having acellular structure (102), said first process having the following stepsin the sequence set forth;

The first step (103) in the first process of manufacture comprising theplacing of said material having a porous structure (104) within a vacuumchamber (105),

The second step (106) in the first process of manufacture comprising thecreation of a vacuum (108) within said vacuum chamber, so that after asuitable interval of time said vacuum extends substantially throughoutthe porous structure (110) of said material,

The third step (112) in the first process of manufacture comprising theapplication of a sealant (113) to the surface (114) of said materialsuch that the vacuum is incorporated within said porous structure and ispreserved against contact with ambient matter,

The fourth step (118) in the first process of manufacture comprising theapplication of a suitable curing process when necessary,

so that after the completion of said first process of manufacture thematerial having a cellular structure (102) is created.

The porous structure of the material used in the first process may becomprised of tubular openings to the surface or microscopic transportapertures that allow the air to escape when the material is exposed tothe vacuum within the vacuum chamber. (The vacuum chamber is representedby the cross-sectional view of the box in FIG. 5.) In step 2, thetransport of the air (The air is indicated by stippling in theillustration of the first step (103) of FIG. 5.) from the porousmaterial and out of the vacuum chamber upon the creation of the vacuumdoes not have to be instantaneous. If it is not, a reasonable length oftime is allowed for the air to transport out of the material uponapplication of the vacuum. When the transport is completed the surfaceof the material is sealed with a suitable sealant. For example, when thematerial is a porous plastic a suitable sealant may be a properlyadmixtured epoxy resin. Or a urethane sealant may also be used.

The sealing of the surface may also involve a suitable curing process asdefined in step 4. But, especially when the sealant is fast setting andthe surface is sealed more or less instantaneously; this may not alwaysbe necessary. For thermosetting plastics the curing process shouldinvolve the application of heat and may or may not involve a chemicalcatalyst. For some materials it may merely involve waiting for thesealant to harden and any excess vapor to be drawn off.

It follows that the porous material need not be plastic but may also bemetal, glass, or any other suitable material. It may therefore bepreferable that said material having a porous structure is a naturallyoccurring material having a porous structure. Such naturally occurringmaterials may be both organic and inorganic. Among the organics we findthe sponges and among the inorganics we have materials such as pumice.It may therefore be preferable that said naturally occurring materialhaving a porous structure is pumice. The pumice is brought into thevacuum chamber and then the chamber is evacuated. After the ambientmatter has been substantially removed from the cells of the pumice thesurface of the pumice is sealed in the presence of the vacuum. Althoughit appears at first glance that polysulfide sealants may be used, theyare known to degrade somewhat when in contact with a vacuum due toout-gassing etc. This may, if the exposure of the poly-sulfide sealantto the vacuum is significant, compromise the sealing function. Ingeneral, sealants that are known to have a high risk for degradationupon contact with a vacuum, are the acrylics, polyamides, polysulfides,and neoprenes. It is therefore preferable that the sealant be selectedfrom a group that may in general function reliably in contact with avacuum, notably the epoxies, urethanes, and silicones. For the sealingof pumice a silicone caulking or sealant composition may therefore bepreferable.

The objective, which is attained by the application of the sealant inthe first process of manufacture for creating a cellular material, isthe preservation of the incorporated vacuum against any influx ofambient matter. This ambient matter may be a particulate, a liquid, agas, or the air of the atmosphere. It may therefore be preferable thatthe ambient matter be air.

According to a further aspect the invention comprises a plurality ofenclosures containing a vacuum, or a plurality of the material having acellular structure that has been created by the first process ofmanufacture for creating a material having a cellular structure, so thatsaid enclosures or said cellular material are dimensioned to comprise aproduct having a size and shape suitable for pouring (FIG. 6, 120), suchthat said product may be poured into holes and cavities, so that thetransmission of sound through said holes and cavities is substantiallyreduced. As also shown in FIG. 6, the product suitable for pouringshould have a size and shape that is substantially uniform. Or puttingit another way, the precursor enclosures or the cellular material thatare used in the creation of a particular body of material or productthat has been produced by the process shown in FIG. 6, should all be ofsubstantially the same size and shape. (A precursor enclosure is anenclosure that is used as an element of a process or method.)

Equivalently sized and shaped enclosures may preferably be used ingeneral, and the preferred order of size for disjointed enclosures to beformed into a cellular material would be from about the size of a smallmarble to the size of a ping pong ball or golf ball. They could also besomewhat bigger, or about the size of a tennis ball or softball. Thissize would preferably fit into a range from about one quarter inch toabout four to five inches. And the enclosures need not be globularspherical or ellipsoidal; rather they could have the shape of anyregular or semi regular three dimensional geometric shape in therequisite size range. In particular they could have the shape of any ofthe regular polyhedrons.

One area of application for this embodiment should be the constructionindustry. Various kinds of buildings may have holes, gaps, spaces orvoids that can admit ambient noise. These gaps may be filled by pouringthe enclosures into them. Although it may be preferable that theenclosures are glass globules or comprise other regular geometric shapes(e.g. a regular polyhedron), the enclosures may also be made of plastic,metal, or any other material that can be fashioned to this purpose.Furthermore, in filling these voids within buildings, the enclosuresshould also aid materially in improving the insulating properties of thestructures.

Inherent insulating properties may be a general advantage of any of theenclosures, whether part of a cellular structure or not. For a largeautonomous enclosure, the addition of a suitable reflective coating tothe inside walls of the enclosure should substantially reduce thetransmission of heat by means of infrared radiation. Although reflectivecoatings may have been used previously to reduce the transmission ofinfrared radiation, their use in building blocks, bricks, or structuralcomponents containing a vacuum may be new. Hence, if the invention isused with this end in mind, both maximal soundproofing and insulatingcharacteristics may accrue to materials or components that alsoincorporate the reflective coating.

When used in the construction industry, the enclosures may also beapplied as a finish to surfaces. The surface (e.g. the exterior orinterior wall of a building) is prepared to accept the enclosures bybeing sprayed with a binding agent or simply by preparing the surfacewith mortar or stucco etc. The enclosures are then applied to thebinding agent, mortar, plaster, putty, or stucco etc., before settingtakes place. For materials that have a moldable surface, such as mortar,plaster, putty, stucco, etc., it may be preferable that the enclosureshave a polyhedral shape, and more preferably the shape of a prism, orthe shape of a tetrahedron. The sharp vertices of these polyhedrons willthen sink into and find anchor in the moldable material. And adecorative enamel or finish may also be applied to the enclosures intheir manufacturing prior to their use in the finishing of surfaces.

Although the enclosures dimensioned to comprise a product suitable forpouring may be loosely poured into requisite holes, gaps or spaces it isalso possible to add a suitable binding agent to fill in the air voidsbetween the enclosures. For example, using a nylon filler in conjunctionwith glass globules or other regular geometric shapes (e.g. a regularpolyhedron) containing a vacuum would allow the creation of a mixturefor the elimination of air voids. Such a mixture may, after applying asuitable catalyst when necessary, set to form a material having acellular structure. And this material should have a shape conforming tothe holes, gaps, spaces, or voids within which the enclosures arepoured, in effect functioning as a filler insulator and sound bafflingmaterial. Accordingly it may be preferable that the invention iscomprised of a plurality of the product having a size and shape suitablefor pouring and having a spatial distribution within a hole or cavity,said plurality further having a suitable binding agent added to form amixture within said hole or cavity, so that said binding agent and saidplurality form a cellular material within said hole or cavity.

As shown in FIG. 6 according to another of its aspects the invention iscomprised of a second process of manufacture that uses the producthaving a size and shape suitable for pouring to create a compositecellular material, said second process having the following steps in thesequence set forth;

the first step (124) in the second process of manufacture comprising thecreation of said product (120),

the second step (128) in the second process of manufacture comprisingthe addition of a suitable binding agent (130) to said product, suchthat said binding agent and said product form a mixture (132),

the third step (134) in the second process of manufacture comprising theapplication of a shaping means (136) to said mixture, such that saidmixture assumes a preferred shape,

the fourth step (137) in the second process of manufacture comprisingthe application of a suitable curing process when necessary,

so that a composite cellular material (122) is created upon thecompletion of said second process of manufacture.

This second process of manufacture shows how to create a compositecellular material from independently created enclosures and/or how tocreate a composite cellular material from blocks of cellular materialcreated by the first process of manufacture. The independent enclosuresor the blocks of cellular material are first combined with a suitablebinding agent. A suitable shaping means is then applied. When theproduct used is comprised of plastic, this may be any one of the knownmethods of centrifugal casting, injection molding, contact molding etc.A curing process may then follow when necessary. For example, when usingan epoxy resin with a product comprised of plastic a fatty amine curingagent may be used.

The binding agent used may also be a plastic, which may or may notrequire a catalyst, retardant, accelerator, etc. It may therefore bepreferable that the binding agent for said product is a plastic incombination with the catalyst required for said second process ofmanufacture. The catalyst is optional depending on the plastic. Forthermosetting plastics it may simply be heat.

Alternatively, the product may simply be a plurality of glass globulesor other regular geometric shapes (e.g. a regular polyhedron), to whichis added a binding agent comprised of glass fibers. The glass globulesor other regular geometric shapes and the fibers may fuse under theapplication of heat. It may therefore be preferable that the productused in said second process of manufacture is comprised of glassglobules or other regular geometric shapes containing a vacuum. It is asimple matter to use a plastic resin in conjunction with the glassfibers. This may produce a cellular material comprised of fiberglasshaving the glass globules or other regular geometric shapes embeddedwithin it.

Fibers comprised of the same material as the enclosure precursors may beused in general to aid in a fusing process. For metal enclosureprecursors metal fibers may be used. These may not always be of the samemetal as the enclosure precursors; it might be preferable to use nickelfibers with steel enclosure precursors or zinc fibers with brassenclosure precursors etc. On the other hand, a general process forfacilitating fusion would of course comprise the use of the samematerial fibers with the same material enclosure precursors. (‘Enclosureprecursor’ is simply a label for an enclosure that may be used as aprecursor in a contemplated process.)

It would therefore be preferable, when fusing the enclosure precursors,that glass fibers are used with glass enclosure precursors,thermoplastic fibers are used with thermoplastic enclosure precursors,and metal fibers are uses with metal enclosure precursors.

Alternatively, it may often be preferable to use a glass with a metal ora plastic with a glass. This, as said before, could involve embedding aplurality of glass enclosure precursors in a binding matrix of nylon.But it may also be preferable to embed a plurality of metal enclosureprecursors in a binding matrix of glass; the metal enclosures are simplymixed into the molten glass. Or the metal enclosure precursors can bemixed into a binding agent comprised of molten plastic. The operativeprinciple here is to strive for a combination of binding agent andenclosure precursor materials that have a ratio of their characteristicimpedances at about one to ten (where the enclosure precursors have atleast ten times the characteristic impedance of the binding agent). Thisshould increase internal acoustic reflectance in the resulting material.

A further process comprises the use of a binding agent in an environmentof less than atmospheric pressure. The enclosures are mixed with thebinding agent and then placed in a vacuum chamber. The pressure in thevacuum chamber is reduced until the binding agent begins to boil: thiswill happen at about the vapor pressure of the binding agent. When thebinding agent solidifies it will contain bubbles containing bindingagent vapor at about the vapor pressure of the binding agent. Thisprocess reduces the amount of binding agent needed and decreases theoverall weight of the resulting cellular material. Any excess bindingagent created by the boiling stage should be drawn off. Alternatively,the binding agent may be administered in an amount just sufficient tobind the enclosures into a cellular material upon boiling.

When fusion is used it may be preferable to use a form that fullyencloses the glass ellipsoids or other regular geometric shapes (e.g. aregular polyhedron). The form will be capable of some contraction sothat pressure may be applied to the glass spheres or other regulargeometric shapes (e.g. A cube with a square cover; the cube is filledwith the enclosure precursors and the cover applies the contractingforce or pressure.). As soon as heat is applied and the glass spheres orother regular geometric shapes reach a malleable state, pressure isapplied by the form, and the spheres or other regular geometric shapesare squeezed together to eliminate voids between the spheres or otherregular geometric shapes. When using fusion, this can be done with orwithout the catalytic aid of the material fibers in the fusing process.Of course the enclosures may have any shape, a spherical shape, anellipsoidal shape, or the shape of any regular polyhedron.

This process may be applied to produce a cellular material in the shapeof the enclosures detailed by reference numbers used in the intervalfrom (138-279) in the specification below. The form would have the shapeof the corresponding enclosures. Therefore the resulting material wouldalso have the shape of the corresponding enclosures. Of course, anyshaping means used in a process for forming a cellular material would beable to construct these shapes as well.

If glass globules or other regular geometric shapes (e.g. a regularpolyhedron) are used an appropriate binding agent may also be nylon 6/6.For example, when contact molding is used, generally a gelatin coatresin is laid up against a polished and waxed mold The nylon laminatingresin and the glass globules or other regular geometric shapes are thenlaid on. Also heat may be used as a catalyst to accelerate this process.It may therefore be preferable that said binding agent is nylon and theenclosures are glass globules or other regular geometric shapescontaining a vacuum.

Spheres or ellipsoids may also be used to construct a vacuum capacitor.A vacuum capacitor (760) should be designed to imitate the properties ofa vacuum chamber, to function as a repository for a vacuum. But a vacuumcapacitor is superior to a vacuum chamber in that it allows a largeamount of vacuum to be created more quickly in the associated vacuumsystem and is also capable of sourcing more than one vacuum.

A vacuum capacitor may be constructed from spheres (762), ellipsoids, orregular polyhedrons, although any shape of enclosure may be used. Whenusing spheres, the spheres are arranged in any well known arrangement(e.g. a face centered cubic structure) and valves (764) and a pipingnetwork (766) are added, with at least one valve being added for eachsphere. The valves may be located in the central space created withineach tetrahedral packing of spheres. Each valve is subject to controlfrom the controlling means and the controlling means has a logic map,which contains a record of the overall geometry of the vacuum capacitoras well as current information detailing the contents of the enclosuresin the vacuum capacitor, and a description of the overall arrangement ofspheres and valves and how they are connected by the piping network.

All spheres are kept at the same high level of evacuation by the meansfor admitting and removing. When vacuum is required in an enclosure oneof the spheres is accessed by opening its valve and the enclosure isconnected to that sphere by the controlling means and the pipingnetwork. (Connected here implies that the requisite valves are opened sothat the fluid contained in the instant sphere and the enclosure canequilibrate. When the pressure between the enclosure and the instantsphere has equilibrated, the valve is closed isolating this sphere fromthe enclosure. Next a second sphere is connected to the enclosure andthe process is repeated until the level of vacuum in the enclosure isthe required level. And concurrently, previously accessed spheres can beevacuated to their highest vacuum state. Sensors (768) located withinthe spheres provide the means for measuring with current information onthe instant pressure that is present within the spheres. This allows thecontrolling means to focus the means for admitting and removing toevacuate only those spheres that have a high internal pressure and toselect spheres at the desired level of evacuation for reducing pressurewithin the enclosures Although FIG. 30 shows the sensors as having aseparate data bus, in practice it may be preferable to run the sensorwires through the piping network. When a piping network is available itis usually more convenient to run sensor cable or wire through or inconjunction with the piping network. This may also reduce the chance ofleakage from the vacuum system.

The advantage of this embodiment lies in the fact that equilibrationoccurs more rapidly and efficiently and that more than one enclosure canbe equilibrated at any one time. The spheres are constructed toapproximately the average size of the enclosures. Therefore with eachseparate access of the vacuum capacitor the pressure in the enclosure issubstantially halved so that on access to succeeding spheres thepressure varies as ½, ¼, ⅛, etc. In comparison a regular vacuum chamberhaving twice the size of an average enclosure could only create onethird the pressure in the enclosure before having to be re-evacuated.The physical elements of a vacuum capacitor can also be used as astorage chamber, or a mixing chamber, or a matter density reservoir.

Another advantage of using a cellular material containing a vacuum isthat for some embodiments the material may be milled to specificationwithout loosing the ability to baffle sound. This is because only thosecells which are at the surface being milled loose the ability to bafflesound, due to rupture being induced by the milling process. It maytherefore be preferable that the invention is comprised of a cellularmaterial or composite cellular material that is workable, so that it maybe shaped to spatial specifications.

In practice, it may be desirable to create blocks or sizable solidaggregations of the cellular material and then reduce these aggregationsinto sheets by cutting or sawing or by any other suitable method. Thethickness of the desired sheets then becomes relevant in determining thesize of the enclosure or sphere or ellipsoid precursors. It has beenfound that to obtain substantial efficiency with regards to sound orthermal baffling of the ambient sound or thermal energy, it ispreferable that the sheets be comprised of at least three layers ofwhole enclosures or ellipsoids. In this regard, it has also been foundthat the maximum cross-sectional distance through a sheet comprised ofthree layers of spheres is about 2.73 times the sphere diameter.Therefore, since there should be at least one cutting layer (the layerthat is destroyed in making the cut) for every sheet, four layers ofenclosures should be required for the making of one sheet of cellularmaterial. It follows that the cuts through a block of cellular materialshould be made in increments of about 3.185 times the sphere diameter.The diameter of the requisite enclosures can then be obtained bydividing the desired thickness of the sheet by about 3.185; for a oneinch thick sheet one would therefore expect the spheres to be about 0.31inch in diameter. And this calculation holds for regular polyhedrons aswell. One merely inscribes a sphere within the polyhedron and proceedingas before calculates the diameter of the sphere and from that deducesthe size of the polyhedron.

It is also possible to create the appropriate sheet thickness bycreating one sheet at a time. A form is prepared and according to thesize of the form and the size of the enclosures contemplated, the numberof these enclosures required to fill the form is calculated. Oneenclosure contributes about 0.91 of its diameter to any linear distancein respect of which it comprises part of a spherical packing. So for afive by five or twenty five square feet form, when using enclosureshaving one inch diameters we obtain 60/0.91=65.93 enclosures in eitherdirection; the total number of enclosures for one layer is then about4347 enclosures and for the full sheet we have three times that orapproximately 13040 enclosures for the whole sheet.

The requisite number of enclosures (13040) can then simply be pouredinto the form. Next the form is subjected to an adjustable shaking orvibrating so that the enclosures assume a three layer packing. When thethree layer packing is achieved the binding agent is poured on tosaturate the voids within the three layer packing, and uponsolidification the sheet is created. Of course this procedure could alsobe used in combination with fusion. And as discussed above, the twosizes proportioned in a ration of one to four; one of the smaller sizedregular solids (e.g. a sphere or ellipsoid) to four of the larger sizedsolids, may be used when constructing these sheets as well.

If economical construction of a cellular material is desired it may bepossible to use waste products such as discarded light bulbs. When lightbulbs are used, care must be taken to use only light bulbs containing avacuum. The light bulbs are then mixed with an appropriate binding agentto eliminate air voids and create a mixture. Next a suitable catalystand shaping means may then be applied. After the mixture has set acellar material wherein each enclosure is comprised of a light bulbcontaining a vacuum is created. Therefore according to a further aspect,the invention is comprised of a plurality of light bulbs containing avacuum for baffling sound, said light bulbs mixed with a suitablecatalyst to create a mixture, so that the solidification of said mixturecomprises a cellular material. And a preferred shape may be formedthough the application of a shaping means to said mixture.

An inexpensive material that can be applied to good effect is corrugatedcard board, suitably sealed by an encasing plastic film or other sealingagent. Each tube (corrugation) of the corrugated card board in effectcomprises a supporting strut. The sealing agent may be a plasticenvelope which is evacuated to vacuum seal the corrugated card boardsuch that the vacuum is incorporated inside the tubes of the corrugatedcard board. The plastic sheet used to vacuum seal the corrugated cardboard will then prevent the entry of ambient matter while the tubularcells of the corrugated card board will counteract the externalpressure.

Effectively this comprises a very low cost embodiment suitable for usein building construction, And sheets of this specially preparedcorrugated card board may further be modified for use in construction byincluding flat nailing strips for attaching the corrugated cardboard totwo by fours and other timber or structural components used in theconstruction industry. Vacuum sealed corrugated card board couldtherefore replace the use of acoustic wool and other building materialsin some applications.

If a material having a cellular structure created from pumice is used,then the appropriate binding agent may be more of the sealant used toseal the pumice. This may comprise adding more of a silicone basedcaulking or sealant composition. Or it may be comprised of a furtherbinding agent and/or filler which may also be mixed with a suitablecatalyst.

And, to guarantee the highest quality for high and ultra high vacuumapplications, it may be preferable to produce the ellipsoids or otherregular geometric shapes (e.g. a regular polyhedron) by using pinch offfor glass, plastic, and metal applications. This involves creating theinitial ellipsoids or other regular geometric shapes with a tubular stemand then hermetically attaching the stem to a vacuum system capable ofpreparing a high or ultra high vacuum. Subsequent to evacuation the stemis pinched off to close the tube and seal the high or ultra high vacuumwithin the ellipsoids. In practice, for those embodiments that are notvariable and are designed to prevent the transmission of sound or tofunction as a thermal insulator, the vacuum may be chosen to have apressure less than 10⁻⁵ Torr, or a pressure less than 10⁻⁸ Torr.Alternatively, for purposes of the present discourse we define thegradations of a vacuum here as; an ultra high vacuum as having apressure less than 10⁻⁵ Pascal, a high vacuum as having a pressurebetween 10⁻⁵ Pascal and 10⁻¹ Pascal, a medium vacuum as having apressure between 10⁻¹ Pascal and 10 Pascal, and a low vacuum as having apressure between 10 Pascal and 10⁵ Pascal.

As shown in FIG. 7 (A, B, C), according to another embodiment it may bepreferable that the shape of the enclosure is selected from the groupconsisting of a sphere (138), a hemisphere (140), a zone and segment ofone base (142), a zone and segment of two bases (144), a sphericalsector (146), a lune (148), a cylinder (150), a cone (152), an ellipticparaboloid (154), a hyperboloid of one sheet (156), a hyperbolicparaboloid (158), an ellipsoid (160), a torus (162), a pyramid (164), amoebius strip (166), a Klein bottle (168), a handle (170), a concavepolyhedron (172), or a convex polyhedron.

It may therefore also be preferable that the invention comprises anenclosure shaped like a convex polyhedron selected from the groupconsisting of a tetrahedron (174), a hexahedron (176), an octahedron(178), a dodecahedron (180), or an icosahedron (182). These regularpolyhedrons are shown in FIG. 8, which also includes a drawing of theprism (184) and the antiprism (186).

As shown in FIG. 9 according to one of its aspects the inventioncomprises an enclosure shaped like a hollow sheet extending in both thex direction and the z direction of the xz plane, the upper (188) andlower (190) surfaces of said sheet having a curvature (192) given bytheir divergence from the xz plane, such that said curvature may bedefined as a function of the y co-ordinate of the xyz co-ordinatesystem.

And as shown in FIG. 10 (A, B, C, D, E) according to another of itsaspects the invention comprises an enclosure shaped like a hollow sheetextending in both the x direction and the z direction of the xz plane,the upper and lower surfaces of said sheet being substantiallyequidistant from each other and having a curvature given by amathematical relationship defined in the xy plane, said relationshipselected from the group consisting of a sinusoid curve, a sine curve(196), an inverse sine curve, a hyperbolic sine curve (198), a cosinecurve, an inverse cosine curve, a hyperbolic cosine curve (208), atangent curve (200), an inverse tangent curve, a hyperbolic tangentcurve (202), a secant curve, an inverse secant curve, a hyperbolicsecant curve (210), a cosecant curve (204), an inverse cosecant curve, ahyperbolic cosecant curve (206), a cotangent curve, an inverse cotangentcurve, a hyperbolic cotangent curve (212), a logarithmic curve (214), aparabola (216), a semicubical parabola (218), a cubical parabola (220),a serpentine curve (248), a trajectory curve, a hyperbola (222), arectangular hyperbola, an equilateral hyperbola, an ellipse (224), acircle, an evolute of an ellipse (226), an involute of a circle (228),an equiangular spiral (230), a hyperbolic spiral, a parabolic spiral, aspiral of Archimedes, a companion to the cycloid, a cycloid (232), awitch of Agnesi (250), a hypocycloid, a deltoid (236), an astroid, anephroid, an epicycloid (234), a cochleoid (246), a stropheoid, aconchoid of Nicomedes, a folium of Descartes (244), a bifoleum (240), alemniscate of Bernoulli, an n-leaved rose (242), an oval of Cassini, alimacon of Pascal (238), a cardioid, a cissoid of Diodes, a lituus, atractrix (FIG. 13, 290), a power function curve, an exponential curve, aprobability curve (FIG. 13, 292), a gamma function curve (252), aquadratic of Hippias (254). Each of these curves may be applied to thesheet, thereby comprising one of the embodiments of the invention. Asshown in FIG. 10 (A, B, C, D, E), although the overall effect is threedimensional, when viewed along the length of the z-axis, the sheetdescribes the selected curve in the xy plane.

The sine curve (196) has the equation y=sin x. When the co-ordinatesystem is not applied the sine and cosine curves are indistinguishable.The same can be said for the secant and cosecant (204) functions.Tangent (200) and co-tangent functions differ to a greater degree. Forsin h (198) we have; sin hx=(e^(x)−e^(−x))/2. Logarithmic (214) curveshave the equation; y=log_(a) x. A parabola (216), semicubical parabola(218), and a cubical parabola (220) have the equations, y=x², y=x^(2/3),and y=x³ respectively. The equation for the hyperbola (222) is also wellknown as x²/a²−y²/b²=1. The equation for the ellipse (224) is also wellknown as x²/a²+y²/b²=1, and where r=a=b, gives the equation of thecircle as x²+y²=r². The evolute of the ellipse (226) is morecomplicated. The co-ordinates for the locus of points on the involute ofa circle (228) are given by x=a cos @+a@ sin @ and y=a sin @−a@ cos @.An equiangular spiral (230) is shown in the drawings, having theequation log r=a@. The witch of Agnesi (250) has an equation ofy=a³/(x²+a²). The locus of the cycloid (232) with the cusp at the originis given by x=a(1−sin @) and y=a(1−cos @). The deltoid (236) is ahypocycloid of three cusps whereas the astroid is a hypocycloid of fourcusps. The general co-ordinates for the locus of an epicycloid (234) aregiven by x=(a+b)cos @−b cos((a+b)@/b), and y=(a+b)sin @−b sin((a+b)@/b).A stropheoid, a conchoid of Nicomedes, and a folium of Descartes (244)are all curves having a very similar shape. The roses (242) may have theequations r=a cos n@ or r²=a cos n@. The limacon of Pascal (238) and thecardioid are also similarly shaped having equations r=b+a cos @ and(x²+y²−ax)²=a²(x²+y²), respectively. The gamma function (252) and theQuadratic of Hippias (254) are two unique multiple curve functions.

When these equations are used to determine a curvature for the enclosurethe resultant appearance of the enclosure is a curved sheet thateffectively follows a straight line in the z direction. However, it maysometimes be desirable to have a curvature in the z direction as well,thereby combining two curvatures. Essentially this involves combiningthe y co-ordinate of the above described curves defined in the xy planewith the y co-ordinate of a further curve selected from the same set ofabove described curves, but further defined in the yz plane. Thecombining of the two y co-ordinates may involve any method of generatinga consistent combination.

The enclosures shown in FIG. 11 exemplify this. The first (262) shows aparabola combined with a serpentine curve. The method of combinationused here is addition. The second enclosure (264) is derived from thecombination of two four leaved roses. The equation defining the roses inthe xy-plane is the same as the equation defining the roses in theyz-plane, with the exception that the latter equation has z substitutedfor x in the former equation. The method of combination is by taking theaverage of the two y co-ordinates. A further enclosure (266) exhibits arather convoluted shape. It is derived from the intersection of twotunnel like enclosures fashioned after the curvature of the Nephroid asdefined in the xy-plane and the curvature of the astroid as defined inthe yz-plane. The method of combination is by subtraction. Lastly wehave the enclosure (272) produced by combining an involute of a circlewith a folium of Descartes by means of division.

It should be noted that a perfect vacuum should not really attenuatesound, if one holds the word to mean decreasing the amplitude of thevolume of the sound volume (This is usually achieved by absorption in asuitable medium). Rather the invention should to a substantial extentoperate to increase the reflection of sound from the vacuum enclosureboundary.

Therefore, when enclosures of a preferred shape and having a preferredstate of rarefaction within them are used to baffle sound a novelacoustic phenomenon results. The reflection from the incident surface isincreased or decreased depending on the state of rarefaction. The lowerthe rarefaction the more sound is transmitted through the enclosure andthe less is reflected. The greater the rarefaction the more is reflectedand the less is transmitted. The baffles as shown therefore allow aportion of the incident sound wave to be divided between the paths ofreflection and transmission. This unique splitting effect is whatconstitutes the characteristic novelty of these embodiments.

The key point here, is that while a sufficiently thin similarly shapedbaffle made of the same material as the enclosure shell will cause asimilar splitting of the incident wave, by adjusting the degree ofrarefaction within the enclosure a much wider range of splittings may beobtained from the same material having the same curvature. And thecurvature of the enclosure is a co-operating element in thiscombination. In a first instance this can be exemplified by consideringthe phenomena of the critical angle of reflection where the highestamount of the incident sound wave is reflected. At the critical angle,increasing the rarefaction of the enclosure should have less effect onthe amount reflected as opposed to what one might expect at an anglethat normally has a high percentage of transmission for the incidentwave. The preparation of a preferred state of rarefaction within theenclosure therefore should not only change the overall percentage ofwhat is transmitted versus what is reflected, it should also change theoverall acoustic angular response characteristics of the enclosure incomparison to what one might expect from simply the uncombined shellmaterial.

Since, as a rule the percentage reflected falls off to either side ofthe critical angle, it follows that a curvature will, by changing theangle of incidence for different loci of the curve, change thepercentage reflected for these loci. When combined with the change inthe overall acoustic angular response characteristics created byrarefaction this should allow for a range of unique, novel andunexpected results, much wider than previously possible by using theshell material on its own.

In summary, for a sufficiently thin shell material capable of soundtransmission, increasing the rarefaction of the enclosure should resultin a larger average reflected component than one would obtain by simplyusing a shell thickness of the shell material on its own. And theoverall acoustic angular response characteristics of the enclosureshould also be different from what the shell material would present onits own. When combined with a preferred shape, the shape and therarefaction may co-operate to produce a range of novel results. And,taking this one step further, one could consider shell effects by takinginto account the splitting of the incident longitudinal wave into atransverse and longitudinal wave upon entry into the solid structure ofthe shell. In short, the curvature is a co-operating element in thestructure of the device.

It may therefore be preferable that the invention also has thecapability to vary the amount and quality of the sound or thermalbaffling provided. The key idea here is that because the presence of thevacuum within the enclosure should make the device essentially opaque tosound transmission, when matter is admitted to the enclosure soundtransmission through the enclosure is enabled. And heat transmissionshould also vary to some extent, increasing as the pressure of thevacuum increases and decreasing as the pressure of the vacuum decreases.The amount of the sound or heat transmission should then be proportionalto the amount of matter that is admitted. And the converse procedureapplies as well. This is illustrated in one part of FIG. 13 according towhich the invention further comprises a means for admitting and removingmatter (288) connected to said enclosures (290, 292) by means of valves(294, 296), so that by admitting and removing matter to and from saidenclosures the sound baffling characteristics of said sound bafflingdevice are varied by said admitting and said removing.

The means for admitting and removing may use some type of vacuum pump toremove the matter from the enclosures. The vacuum pump may be motordriven or operated manually in some applications. After the matter hasbeen removed from the enclosures, it can be readmitted by using theexternal pressure as a driving force. All that is required is a two wayvalve. Such a valve could be used, in either manual or automaticoperation, for either the admitting or removing of matter from theenclosures.

Accordingly, this embodiment exhibits the ability to baffle sound in adynamic fashion. While this may have been done previously by rotating ormoving the enclosures, the invention shows how the admitting andremoving of matter to and from an enclosure may be used to baffle sounddynamically. In general admitting matter to the enclosure shoulddecrease the sound baffling characteristics of the enclosure andremoving matter from the enclosure should increase the sound bafflingcharacteristics of the enclosure. It may therefore be preferable thatsaid admitting increases the transmission of sound through theenclosures and said removing decreases the transmission of sound throughthe enclosures.

Most applications involving dynamic sound baffling will probably requiremore than one enclosure to effectively adjust the ambient sound. Thisfollows from the fact that for many applications, such as the adjustmentof temperature or acoustics in a theater or lecture halls, the ambientthermal or acoustic environment is frequently changing. For example, theentry and exit of people to and from a lecture hall should change thevalues and characteristics of the ambient sound and temperature. Adynamic adjustment of the sound baffling characteristics of the soundbaffling device is therefore required to maintain the acousticcharacteristics close to optimum.

In general the invention may be characterized as having three basicobjects; the controlling of sound, the controlling of heat, and thecontrolling or creation of spatial configurations represented in thefinished enclosures or contiguous aggregates of enclosures. Acontrolling means may therefore be used to control a general class ofvariable elements that effect the execution of the above named objects.A variable element may be defined as any element or subcombination ofthe invention that can be controlled to effectively vary the acoustic,thermal or geometric characteristics of the invention.

In operation the controlling means will at minimum have a plurality ofdefault parametric values and characteristics combined with a pluralityof default tolerances to guide it, and this may include both thermal andacoustic variables. The nature of the acoustic or thermal environment isthen assessed by a means for measuring. The assessment results in thecreation of a plurality of measured values and characteristics, andthese may include both thermal and acoustic variables. After the meansfor correlating examines the correlation between these two pluralitiesthe variable elements of the physical space are adjusted to improve thecorrelation. (In the case of volume transduction this could involveincreasing or decreasing the amount of transduction. Or for frequencymodulating bars residing in an tension and/or compression node this maymean increasing or decreasing the node separation to affirm or negatethe effect of the bars.)

The operation of the controlling means is predictably in step with theplurality of default parametric values and characteristics. But thecontrolling means will also allow input parametric values andcharacteristics to be entered into its electronic memory. Should adifferent adjustment of the ambient sound be desired, a new plurality ofinput parametric values and characteristics can be entered by the user.If these are present, the controlling means will use the correspondinginput parametric values and characteristics instead of the defaultparametric values and characteristics to do its calculation. This allowsthe operation of the controlling means to be adjusted to suit differentuser preferences (for different acoustic or thermal environments).

As previously discussed, the dynamic adjustment of a sound bafflingdevice is best handled by the controlling means. Accordingly, anembodiment of the invention which is designed to handle complexapplications is illustrated in the greater part of FIG. 13, according towhich the invention further comprises a controlling means (298), saidcontrolling means having an input means (300) for entering and storingparametric values and characteristics (302), and;

said controlling means further having a means for measuring (304) thevalues and characteristics of the ambient sound, said means formeasuring having sensor inputs (306, 307) placed throughout the extentof the physical space (308) which is governed by said sound bafflingdevice, and;

said controlling means further having a means for correlating (310) saidmeasured values and characteristics (312) of the ambient sound to saidstored parametric values, and;

said means for correlating using the correlation (314) between saidmeasured values and characteristics of the ambient sound and said storedparametric values as a benchmark for adjusting said means for admittingand removing of matter,

such that matter is admitted and removed from said enclosures asindicated by said benchmark,

so that the measured values and characteristics of the ambient soundthroughout the physical space which is governed by said sound bafflingdevice enter a convergence towards said stored parametric values, and;

after a requisite interval of time an optimum correlation between saidstored parametric values and said measured values of the ambient soundis attained.

Alternatively, for the present filing a more concise description of thisaspect of the invention may be as follows; The controlling means as nowshown in the preferred embodiment of FIG. 38, further having an inputmeans for entering and storing a plurality of input parametric valuesand characteristics, and; said plurality of input parametric values andcharacteristics replacing said plurality of stored parametric values andcharacteristics in operation,

so that said means for correlating uses the correlation between saidplurality of measured values and characteristics and said plurality ofinput parametric values and characteristics as a benchmark for adjustingsaid variable elements of the physical space to improve the correlation,so that said plurality of measured values and characteristics enter saidconvergence towards said plurality of input parametric values andcharacteristics,whereby said optimum correlation between said plurality of inputparametric values and characteristics and said plurality of measuredvalues and characteristics is attained.

The underlying objective of the preferred embodiment is to allow theuser of the sound baffling device to choose the values andcharacteristics of the ambient sound to a degree closely correspondingto the users preferred values and characteristics for the ambient sound.The user may accomplish this by entering the preferred values andcharacteristics as the parametric values and characteristics of theambient sound (302) into the input means (300), whereby they becomeinput parametric values and characteristics. These values andcharacteristics may be any parameter that has been used or may be usedto characterize the sound. However, the input means of some preferredembodiment may not accept the universal historical set of potentialparametric values and characteristics. In such a case the parametricvalues and characteristics of the ambient sound accepted by the inputmeans will be a subset of the universal parametric set of values andcharacteristics of sound.

Values and characteristics that may in general be accepted as parametersby the input means are, loudness, reverberation, and timbre. Furthervalues and characteristics that may be settable are, pitch, attack, anddecay. After the settable values have been entered they are compared tothe measured values and characteristics (312) gathered through the meansfor measuring (304) which has sensor inputs (306, 307) that measure theparametric values and characteristics of the ambient sound throughoutthe physical space (308) governed by the sound baffling device. And themeans for measuring will also have sensor inputs (761, 763, 765) forretrieving a pressure reading from inside the enclosures or chambers andfor measuring the state of a node or force generating means. Thecomparison itself is carried out by the means for correlating (310)which should adjust the sound baffling device through the means foradmitting and removing and/or the pressure varying means if it findsthat the difference between the measured parametric values andcharacteristics and the selected parametric values and characteristicsis sufficiently large as to require adjustment. The adjustment shouldthen create parametric values and characteristics for the ambient soundthat correspond more closely to the selected parametric values andcharacteristics of the ambient sound stored in the input means.

For more complicated scenarios a computer may be added to thecontrolling means. A computer is especially valuable when differenttypes of performances should succeed each other in a theatricalenvironment, or if different types of thermal venues are desired atdifferent times of day. For example a speaker may precede a musicalperformer or it is desired that the nighttime temperature should becooler than the daytime temperature. In such a case more than oneplurality of input parametric values and characteristics may be entered.The microprocessor will then read the input parametric values andcharacteristics when indicated and prompt the means for correlating tocarry out the requisite adjustments. In general a controlling means alsohaving a microprocessor is more adaptable to different performancescenarios and thermal adaptations. Knowledgeable product support staffshould be able to add subroutines to suit ongoing requirements anddifficulties.

Also, in complex acoustic or thermal environments having many shapedenclosures, the large number of variable elements and effects presentedmake the registers and memory banks of a computer a tremendousconvenience. Pluralities of input parametric values and characteristicscan be stored as presets and/or in other appropriate file formats. Laterthey can be recalled by loading or during program operation, therebymaking the tuning of large thermal or acoustic systems feasible.

The knowledge of how to program these problems is readily available inthe computing science and acoustic arts; acoustic ray tracing andacoustic pyramid tracing programs are commercially available. And theyare even available as freeware. One web site that readily comes to mindis ‘http://www.ramsete.com’.

Some references that nay be useful with regards to customizing a programfor acoustic use are:

-   1. A. Farina; RAMSETE—a new Pyramid Tracer for medium and large    scale acoustic problems, Proc. of EURO-NOISE 95 Conference, Lyon    21-23 Mar. 1995-   2. A. Farina; Pyramid Tracing vs. Ray Tracing for the simulation of    sound propagation in large rooms, In the volume “Computational    Acoustics and its Environmental Applications”, pp. 109-116,    Editor C. A. Brebbia, Computational Mechanics Publications,    Southampton (GB) 1995-   3. A. Cocchi, A. Farina, L. Rocco; Reliability of Scale-Model    Researches: a Concert Hall Case, Applied Acoustics vol. 30 no.    1 (1990) pagg. 1-13-   4. A. Cocchi, A. Farina, L. Tronchin; Computer assisted methods and    acoustic quality: recent restoration case histories, Proceedings oh    MCHA95, Kirishima (Japan) 15-18 May 1995    Therefore, according to another of its aspects the invention    comprises the controlling means as shown in the preferred embodiment    of FIG. 28, further having a microprocessor governed by a    controlling program, said controlling program enabling a computer    simulation of the physical space governed by said controlling means,    said model devised to operate in accordance with the principles of    science, and; said controlling program capable of calculating a    plurality of predicted values and characteristics which should    result from adjusting said variable elements, and;    said controlling program further using the correlation between said    plurality of predicted values and characteristics and said plurality    of stored parametric values and characteristics to create a second    benchmark, and;    said controlling program using said second benchmark to calculate    instructions for said means for correlating, and;    said means for correlating using said instructions to adjust said    variable elements of the physical space, so that said plurality of    measured values and characteristics enter a convergence towards said    plurality of input parametric values and characteristics,    whereby an optimum correlation between said plurality of stored    parametric values and characteristics and said plurality of measured    values and characteristics is attained.

The technology used to implement the controlling means (298) may bebased around a microprocessor governed by a controlling program designedspecifically for this task. While optional, the controlling program andmicroprocessor effectively should augment the means for correlatingwhile the other means may be implemented by dedicated hardware. Theinput means may simply be some kind of data entry console as exemplifiedby a PC terminal and keyboard. Or it may be a set of switches inconjunction with LED readouts or dials, as may be deemed mostappropriate for a particular design. The means for measuring should havesensors for testing the ambient sound, the most obvious of which wouldof course be microphones (332, 333) placed strategically throughout thephysical space which is governed by the sound baffling device. Also themeans for measuring should have pressure or rarefaction sensors (751,768) within the enclosures or various chambers etc., and transducers(753, 755) for sensing the state of a node or force generating means.The information from these sensors may then be converted into a digitalrepresentation useable by the means for correlating in carrying out thecomparison of the values and characteristics of the ambient sound. Andthis digital representation should also be useable by the controllingprogram and the microprocessor (334).

The controlling program should contain a thermal or acoustic model ofthe physical space under consideration. This model is derived from, andconstructed in accordance with the principles of thermal or acousticscience and includes the effects of the placement and shape of theenclosures (290, 292) on the values and characteristics of the ambientsound or temperature. And this model is also capable of estimating theeffects of various amounts of matter present within the enclosures onthe ambient sound. By using this model and the input parametric valuesand characteristics as a basis for the initiation of calculations, thecontrolling program should be able to estimate the appropriate level ofmatter that should be present within each of the enclosures. Subsequentto the calculation of this estimate, the controlling program and themicroprocessor should then generate the necessary set of instructionsfor the means for admitting and removing and/or the pressure varyingmeans.

Alternatively, a neural net (754) may be used instead of or inconjunction with a microprocessor. The neural net could be computerbased but it may be preferable to have it hardwired. One advantage of aneural net is that it may be more compact and have a faster responsetime than a microprocessor. The knowledge of how to construct a neuralnet is readily available in the computing science arts. A hard wiredneural net can be constructed by using a programmable read only memorychips (PROM) or an erasable programmable read only memory (EPROM) incombination with a broad array of devices and systems such asProgrammable Logic Controllers (PLC), Programmable Logic Devices (PLD),Programmable Array Logic (PAL), Field Programmable Gate Arrays (FPGA),Application Specific Integrated Circuits (ASIC), System-on-Chip (SOC),and Complex PLD (CPLD) that can be utilized for digital logicimplementation and control.

Also Field Programmable Gate Arrays (FPGAs) can be employed tostandardize functionality formerly performed by a CPU, and to createcustom capabilities (e.g. science domain specific massively paralleldata compression). Programmable logic software can be tested forfunctionality, boundary conditions, and operational simulation byadapting existing methods such as Fagan and Gibbs inspection of softwareat the Design Review level, as well as for Quality Assurance. A (VeryLarge Scale Integration; VLSI) hardware design language that isparticularly suited as a language for describing the structure andbehavior of digital electronic hardware designs, such as ASICs and FPGAsas well as conventional digital circuits could then be used to createthe hardwired neural net. Or the neural net could simply be softwarebased and could then be operated in conjunction with the microprocessor.

Therefore, according to another of its aspects the invention comprisesthe controlling means as shown in the preferred embodiment of FIG. 28,further having a neural net enabling an electronic simulation orcomputer simulation of the physical space governed by said controllingmeans, said electronic simulation or computer simulation devised tooperate in accordance with the principles of science, and;

said neural net capable of calculating a plurality of alternatepredicted values and characteristics which should result from adjustingsaid variable elements, and;

said neural net further using the correlation between said plurality ofalternate predicted values and characteristics and said plurality ofstored parametric values and characteristics to create a thirdbenchmark, and;

said neural net using said third benchmark to calculate instructions forsaid means for correlating, and; said means for correlating using saidinstructions to adjust said variable elements of the physical space, sothat said plurality of measured values and characteristics enter aconvergence towards said plurality of stored parametric values andcharacteristics,whereby an optimum correlation between said plurality of storedparametric values and characteristics and said plurality of measuredvalues and characteristics is attained.

The construction of neural nets is well known in the art. Rudimentarily,there are three main types of nets:

1. A multilayer net using back propagation

2. A Hopfield net

3. A Kohonen net

A detailed discussion of these and other neural nets may be found at‘http://www.shef.ac.uk/psychology/gurney/notes/index.html’. Also thefollowing references are recommended:

-   1. Graf, H., Hubbard, W., Jackel, L., and deVegvar P. G. N (1987). A    CMOS associative memory chip.-   2. Gorman, R. P. & Sejnowski, T. ‘Analysis of hidden units in a    layered network trained to classify sonar targets’, Neural Networks,    1, 75-89.-   4. Hopfield, J. (1982). Neural networks and physical systems with    emergent collective computational properties. Proceedings of the    National Academy of Sciences of the USA, 79:2554-2588.-   3. In 1st Int. Conference Neural Nets, San Diego, Hopfield, J. and    Tank, D. (1985). Neural computation of decisions in optimization    problems., Biological Cybernetics, 52:141-152, Kohonen, T. (1984).    Self-organization and associative memory. Springer Verlag.

It follows that the combinations of controlling means, microprocessor,and neural net, may be used to control the variable element discussedbelow. This class of variable elements may, in its basic form, becomprised of the force generating means in all their variations, certainnodal means having an active effect on the attaining of the above namedobjects, and energy transfer elements, such as transducers, that have aspecific and useful technical function. We list the energy transferelements as follows:

-   -   1. enclosure transduction circuit—changes the sound output        emanating from the enclosure wall distal to the sound source;        generally resides in a transduction node    -   2. frequency modulating bars or disks—this is simply a grouping        of bars or disks mounted on a column or strut that changes the        frequency of the sound traveling through it.    -   3. valves—these are simply valves that can be used to regulate        the homogeneous fluid matter flow from a means for admitting and        removing or a pressure varying means to and from the enclosures        as required by a controlling means.    -   4. tension and/or compression node—these are node having the        ability to expand or contract the enclosure    -   5. retracting nodes—these are nodes having the ability to        retract within or without an enclosure thereby creating a nodal        gap so that the transmission of sound or thermal energy across        the nodal gap is substantially barred    -   6. actuator—usually allows force to be applied linearly and        usually relies on an electric (magnetic), hydraulic, or        pneumatic force to provide the actuation.    -   7. electric motor—this may be used to rotate or translate the        enclosure. Or it may be used to tighten or loosen lines or move        levers or operate a hydraulic or pneumatic reservoir for        hydraulic force generating means or a pneumatic force generating        means    -   8. force generating means—these means change the geometric,        thermal, or acoustic properties of an enclosure    -   9. RF transmitter—this can be used to provide measured values        and characteristics to the controlling means and can be used to        receive information and instructions for active elements in the        enclosure from the controlling means

It may therefore be preferable that according to one of its aspects theinvention further comprises a variable element that is selected from thegroup consisting of a noise canceling transducer, a transductioncircuit, frequency modulating bars, frequency modulating disks, aretracting node, an tension and/or compression node, a valve, anactuator, and an electric motor.

It may therefore be preferable that the enclosures also have anenclosure transduction circuit. The enclosure transduction circuitshould have an input signal transducer (800, 801), which should usuallybe a piezoelectric transducer, although it may also be a contacttransducer, a magnetic transducer, or possibly a microphone, as suitablefor a specific application. The enclosure transduction circuit shouldalso have at least one output signal transducer (804) which shouldusually be a matched piezoelectric transducer, but could also be acontact transducer, a magnetic transducer, or possibly a speaker as maybe suitable for a specific application. It should be preferable to matchthe input and output transducer to achieve a matched pair. By ‘matched’is meant the optimum companion transducer, one that necessitates theleast electronic circuitry and manipulation to achieve the desiredresult. The transducers should be mounted on or in a supporting strut orcolumn (806) or in the frame (808) of the enclosure, in what shouldgenerally be called a transduction node. These transducers should bemanufactured to pick up or emit sound, in the audible range, to areasonable degree of fidelity. The input signal transducer should bemounted in that part of the supporting strut or column or frame, whichfirst receives the incident or direct sound wave (802) traveling throughthe physical space under consideration. The output signal transducershould then be mounted behind the input signal transducer (‘Behind’means that the direct sound wave reaches the input signal transducerfirst.), the exact positioning to be determined by the type of enclosuretransduction circuit.

There are five basic enclosure transduction circuits: noise canceling,sound canceling, modulation, modulated noise canceling, and modulatedsound canceling. And when structural frames and columns composed ofmaterials having different acoustic impedances are used another fivederivative transduction circuits may be formed.

A noise canceling circuit may be created, as shown in FIG. 40 A, byplacing the output signal transducer shortly behind the input signaltransducer, so that unwanted noise is removed from the input signal(810). Noise canceling circuits have been shown before, but to theapplicants knowledge, they have not been used to cancel noise in asolid. The noise canceling transduction circuit will send the inputsignal to the microprocessor or the neural net, where the input signalis treated to comprise the output signal (812). As can be seen byexamining (810 and (812), the output signal contains a bar of noise thatwill cancel the bar of noise in the input signal. This results in asubstantially noise free wave form for any sound that continues totravel through the frame and/or the supporting strut.

If structural frames and columns composed of materials having differentacoustic impedances (Normally, for increasing internal reflection, thecharacteristic impedance of the material facing the direct sound wave ischosen to be at least or about one tenth the characteristic impedance ofthe backing material.) are used, then the noise canceling circuit willbe placed in the facing material before the join to the material ofhigher acoustic impedance.

Alternatively, the enclosure may comprise a sound canceling circuit.This circuit should normally be added to structural nodes in anenclosure with the intent of preventing substantial sound transmissionthrough the supporting columns or crossbars of the structural nodes,and/or the frame of the enclosure. In this application the music orambient sound picked up by the input transducer is characterized asnoise by the microprocessor or neural net. As a result the output signalis calculated by the microprocessor or neural net to exactly cancel theinput signal as created by the direct sound wave. This should result insubstantially total sound cancellation in the supporting columns orcrossbars of the structural nodes, and/or the frame of the enclosure.

If structural frames and columns composed of materials having differentacoustic impedances are used, then the sound canceling circuit will beplaced in the facing material before the join to the material of higheracoustic impedance.

For rudimentary acoustical considerations, only four basic variablesshould require consideration; the listening level which is the volume ofsound experienced by an audience member during a performance, theinitial time delay gap, which is the delay of the first reflectionmeasured from the time of arrival of the direct sound wave at alistening point, the reverberation time which is defined as the timenecessary for a decay of 60 DB of the sound field after the sound sourcehas been turned off, and the inter aural cross correlation which isdefined as the maximum value of the normalized cross-correlationfunction of two impulse responses measured by two microphones placed ina dummy head's auricular lobes. These variables should also be includedin the list of default parametric values and characteristics, and besettable by the input means as input parametric values andcharacteristics. It may therefore be preferable that the enclosuretransduction circuit is also used to modulate these variables whendesirable and feasible.

To carry out modulation of these and other variables the inputtransducer should generate an input signal that is then analyzed by themicroprocessor and/or neural net. It may usually be preferable to putthe input signal through an analog to digital converter. After the inputsignal has been converted to digital form it may be modified to exhibitpreferred characteristics that are then combined with the input signalto generate the output signal. The output signal is then applied to theoutput transducer. In this way the enclosure may, in addition toreflecting, absorbing, and refracting the sound, also add preferablefeatures such as a change in volume, a change in the initial time delaygap, a change in the inter aural cross correlation, a change in pitch(pitch bend), a change in timbre, a change in harmony, a change inreverberation time, and a change in meter or rhythm (possibly by addinga beat).

In particular the volume may be increased by increasing the volume ofthe output from the output transducer. The inter aural cross correlationcan be affected by varying the output signal from the output transducerbetween two enclosures on opposite sides or in different parts of thephysical space under consideration. The initial time delay gap can bemodified by playing an output signal from the enclosure before it wouldnormally be played in that part of the physical space where theenclosure resides; this requires that an earlier version of the signalbe sent from the microprocessor and/or neural net combination to theenclosure directly before the direct sound wave actually arrives in thevicinity of the enclosure. This would normally be done by using theinput signal from an enclosure that is closer to the sound source,performing the appropriate modifications on this input signal and thensending the produced output signal to the more distant enclosure whereit is applied to the output transducer. Similarly, an output may beproduced by the enclosure after the sound source is turned off, andthereby affect the reverberation time.

If structural frames and columns composed of materials having differentacoustic impedances are used, then the sound modulating circuit willpreferably be split, with the input transducer residing in the facingmaterial before the join to the material of higher acoustic impedance,and the output transducer residing after the join in the material ofhigher acoustic impedance.

The sound modulating circuit can be combined with the sound cancelingtransduction circuit above to create a modulated sound cancelingtransduction circuit. This means that the incident sound issubstantially canceled out of the supporting struts and frame of theenclosure so that the sound added by the output transducer, if any, issubstantially created by the microprocessor and or neural net. Thecombined circuit should then be called a modulated sound cancelingtransduction circuit. The modulating transducer is placed last in linewith regards to the direct sound wave; this enables it to add soundgenerated by the microprocessor and/or neural net after the direct soundin the columns or frame of the enclosure has been substantiallyeliminated.

If structural frames and columns composed of materials having differentacoustic impedances are used, then the modulated noise cancelingtransduction circuit will preferably be split, with the input transducerresiding in the facing material before the join to the material ofhigher acoustic impedance, along with the output transducer, while themodulating transducer resides after the join in the material of higheracoustic impedance.

This sound modulating circuit can be combined with the noise cancelingtransduction circuit above. This means that the extraneous noise issubstantially canceled out of the supporting struts and frame of theenclosure. The combined circuit should then be called a modulated noisecanceling transduction circuit. The modulating transducer is placed lastin line with regards to the direct sound wave; this enables it to addpreferred acoustic information generated by the microprocessor or neuralnet after extraneous noise in the columns or frame of the enclosure hasbeen substantially eliminated.

If structural frames and columns composed of materials having differentacoustic are used, then the modulated sound canceling transductioncircuit will preferably be split, with the input transducer residing inthe facing material before the join to the material of higher acousticimpedance, along with the output transducer, while the modulatingtransducer resides after the join in the material of higher acousticimpedance.

It may be preferable to use radio frequency technology as exemplified byRF tags. This technology may be implemented to provide a more convenientconstruction of the sensor network required by an ensemble of enclosuresconnected to a controlling means, as exemplified by the use oftransducers in combination with a controlling means above. The use of RFtags is simply substituted for the use of wires connected to sensors.

As shown in U.S. Pat. No. 5,457,447, RF technology or transmitted energymay also be used to supply power to an RF tag that may be used tocomprise a sensing circuit as may be preferable in some applications, inparticular to provide measured values and characteristics to a means formeasuring. And as shown in U.S. Pat. No. 6,107,917 and U.S. Pat. No.6,061,614, RF technology is also capable of using RF tags to receiveinstructions from the controlling means and in turn is equally capableof returning requisite information to the means for measuring. Theseprior art of these patents can therefore be used in the RF tags of thepresent invention and the disclosures of said patents are accordinglyincorporated herein in their entirety by reference.

Therefore it may be preferable that the enclosures also comprise RF tagspowered by line current or, alternatively coupled to an RF powered powersource capable of providing the power needs of the RF tags. And it mayfurther be preferable that the RF tags receive and execute instructionsfrom the controlling means and send measured values and characteristicsto the means for measuring as required in the effective operation of theinvention.

Noise reduction and cancellation has had extensive treatment in the artand a number of references may be useful: U.S. Pat. No. 6,917,688, U.S.Pat. No. 6,363,345, U.S. Pat. No. 6,285,768, U.S. Pat. No. 6,937,070,U.S. Pat. No. 5,937,070, U.S. Pat. No. 5,748,749, U.S. Pat. No.5,740,256, U.S. Pat. No. 5,639,997, U.S. Pat. No. 5,214,965, U.S. Pat.No. 5,204,907, U.S. Pat. No. 5,138,663, U.S. Pat. No. 5,134,659, U.S.Pat. No. 4,911,054, U.S. Pat. No. 4,821,241 U.S. Pat. No. 4,760,279,U.S. Pat. No. 4,127,749, U.S. Pat. No. 3,995,124. Transducers in theaudible range can be obtained from the supplier of transducers and thesuppliers of musical instruments and transducers.

Although the enclosure could also be considered a variable element,since it is usually the recipient of an action (e.g. A change in thelevel of rarefaction created through the actions of a means foradmitting and removing) it is generally not considered so. The actualelement that carries out the action is considered to be the variableelement, since this is the element that will receive instructions fromthe means for correlating. And for the enclosure the primary elementthat usually carries out actions on the enclosure is the forcegenerating means (799). These fall into three main categories, forcegenerating means that change the geometrical properties of the enclosureby transforming a flexible enclosure into a different shape, forcegenerating means that change the acoustic properties of the enclosure,and force generating means that change the thermal properties of theenclosure. Of course changing the shape of the enclosure may change theacoustic properties and thermal properties as well. In this regard, themost elementary transformations of the acoustic properties and thethermal properties of course depend on simply changing the energyconductivity of the enclosure with regards to the relevant energy, soundfor the acoustic properties and heat for the thermal properties. Thiscan be done by, instead of using a pressure varying means or a means foradmitting and removing, simply changing the amount of contact betweenthe enclosure walls or between nodes in the enclosure walls.

According to another of its aspects the invention is embodied as anenclosure comprising a force generating means, so that the geometricalproperties of said enclosure, or the acoustic properties of saidenclosure, or the thermal properties of said enclosure, can be varied bysaid force generating means. And the enclosure may also contain ahomogeneous fluid for attenuating sound or heat, and further comprise apressure varying means.

The homogeneous fluid for attenuating sound or heat will of course beeffective for preventing both heat and sound transmission through theenclosure. As has been discussed elsewhere, the effect of varying thehomogeneous fluid for attenuating sound or heat in the enclosure shouldbe to change the impedance of the enclosure for both heat and sound. Asound absorbing material applied to the rear wall of the enclosure wouldtherefore add sound absorbing characteristics when the impedance of theenclosure is minimum That is to say, when the enclosure is placedagainst a wall with the sound absorbing material facing the wall and theimpedance is high, the sound will be largely reflected from theenclosure. But when the impedance is low the sound will travel throughthe enclosure and be absorbed by the sound absorbing material.

Therefore according to one of its aspects the invention comprises; ansound absorbing material contacted to a wall of said enclosure, so thatwhen the impedance of said enclosure is minimized, the sound absorbingcharacteristics of said enclosure are substantially increased.

Alternatively, the sound absorbing material could also be placed intothe interior of the enclosure, as long as the sound absorbing materialis prevented from contacting the enclosure walls directly when theimpedance of the enclosure is high. Or the sound absorbing materialcould be placed between two enclosures that can be controlledindependently. When both enclosures exhibit a high acoustic impedancethe sound absorbing material has little or no effect on the ambientsound. When one enclosure exhibits a high acoustic impedance and theother enclosure does not, the side of the embodiment where the enclosurehas a low acoustic impedance experiences significant sound absorption.And for a setting having an intermediate impedance some sound will bereflected while other sound will be absorbed. By varying the impedancethe user of the invention will be able to choose between levels ofabsorption and reflection with this embodiment. This embodiment istherefore preferably used when the enclosure is hanging freely in thephysical space under consideration, since it allows the sound to beabsorbed or reflected from either side, as may be preferable.

Therefore according to another of its aspects the invention comprises; asound absorbing material contacted on a first side to a wall of a firstenclosure, said sound absorbing material contacted on a second side to awall of a second enclosure,

so that when the impedance of said first enclosure is minimized, saidsound absorbing material substantially absorbs the sound travelingthrough said first enclosure, and when the impedance of said firstenclosure is maximized, said first enclosure substantially reflects allof the sound in the direct wave, and;when the impedance of said second enclosure is minimized, said soundabsorbing material substantially absorbs the sound traveling throughsaid second enclosure, and when the impedance of said second enclosureis maximized, said second enclosure substantially reflects all of thesound in the direct wave;whereby sound can be variably reflected or absorbed. Similarly, a singleenclosure having flexible walls could be wrapped around a length ofsound baffling material. Although this enclosure would not havevariability on two sides, it would have the same variability on bothsides.

It may also be advantageous to maintain surface tension across thesewalls to retain optimum reflective properties when a distending orcontracting force is applied. This may be done by adding a resilientborder to the perimeter of the enclosure. A resilient border may be madefrom stainless steel spring wire or a flexible plastic moulding, orhydraulic or pneumatic tubing under pressure. But the footprint of theborder should be minimized to avoid interference with the ambient sound.

It may therefore be preferable that according to one of its aspects theinvention further comprises; an enclosure having at least one flexiblewall, said enclosure further comprising a resilient border formaintaining an optimum surface tension across said at least one flexiblewalls, so that said at least one flexible wall presents a smoothreflective surface to the incident sound.

When the enclosure has flexible walls, the border may also be comprisedof a pneumatic force generating means in combination with a spring forcegenerating means. The spring force generating means is used to retractthe enclosure when not in use and the pneumatic force generating meansis uses to extend the enclosure for use. In some embodiments thepneumatic force generating means may also be used to fashion a resilientborder.

In general for an enclosure to be effective it is necessary incorporatea force generating means into the enclosure. This is because in use,when the enclosure is evacuated, large pressures should becounterbalanced to maintain the structural integrity of the enclosure.Alternatively, when the enclosure is pressurized, large internalpressures should be counterbalanced to maintain structural integrity.While this may be done by building a sufficiently sturdy enclosure withstrong supporting struts, braces, and crossbars, in practice it ispreferable to produce enclosures that are of light construction andminimize the amount of material used to construct the enclosure walls.

The reason for this is simply that the maximum benefit of the activemedium in the enclosure is obtained when the impact of the enclosurewalls and frame on the ambient sound and the direct sound wave isminimized Since the absorption of sound energy or thermal energy isproportional to the thickness of the walls, the thinner the walls, theless sound energy or thermal energy will be stored or absorbed in thewalls. (Of course sound energy is converted into thermal energy onabsorption.) And thermal energy will be stored and potentially laterreleased when the ambient temperature drops below the temperature of thewalls. Therefore it is desirable to minimize the wall thickness as muchas possible while still ensuring that the enclosure retains its hermeticproperties.

The walls therefore should be thin but the option of having themstructurally fixed or flexible remains. Of course a wall that issufficiently thin will tend to be flexible and will twist or buckleunder the application of pressures. If the wall is intended to be fixedthen supporting struts applied at appropriate intervals will remedy theproblem. These supporting struts could be internal or external butbecause of the tendency for external structures to interfere with thetransmission of sound it may be preferable to have the supporting strutsinternal. For purely thermal applications it may on occasion bepreferable to have the supporting struts for the enclosure appliedexternally.

Supporting struts may be considered to be the first of a large number offorce generating means that can be applied to the enclosure eithersingly or in combination. The actual force generating means to beapplied will vary depending on the type of enclosure, whether it is anenclosure having flexible walls, or whether it is an enclosure havingfixed walls. The majority of force generating means may be applied toenclosures having flexible walls and may in general comprise the use oftension and/or compression nodes, while force generating means appliedto fixed wall enclosures may in general comprise the use of retractingnodes. And simple rotation or translation of the enclosure may also becarried out by a force generating means.

The actual force generating means may be applied internally orexternally. But it should generally be preferable to apply the forcegenerating means internally to the enclosure to minimize interferencewith the direct sound wave. The one exception is of course the lineforce generating means, which is in general applied externally.

In creating the enclosures it is important that the stress that may beplaced on the components be taken under consideration. Stress can causeshear failure and must be considered in selecting and sizing materialsfor any construction that requires the handling of large forces. Anddepending on the degree of evacuation or internal overpressure, theenclosures may indeed have to handle large forces.

In fact, just one square foot of a sound baffle will have over a ton ofpressure on it under full evacuation. The way of dealing with this mayof course be by simply dividing the pressure or force over a largenumber of supporting struts. For a square foot of a sound baffle thismight be done by using 144 supporting struts that would then deal with apressure of 14.7 lb. P.S.I. each, under full evacuation. At one halfatmospheric the pressure would be less, or about 7.35 lb. P.S.I. In anyevent it would be preferable to use fewer supporting struts, ifpossible.

A few simple stress hints might be appropriate here, although morecomprehensive information can be found in (R. J. Roark and W. C. Young,Formulas for Stress and Strain, 5th ed., New York, McGraw-Hill, 1975).To begin with, the actual strut would normally not have a one squareinch cross section; a rectangular strut cross section is just base timesheight (b×h) or width times length, and a circular strut cross sectionis given by πd²/4. The compressive stress is then given by σ=F/A, whereF is the pressure or force on the strut.

Therefore a one eight inch diameter strut carrying one square inch ofthe enclosure surface at 14.7 P.S.I, would have about 14.7/.01127=1198P.S.I. of pressure exerted on it. The procedure in selecting the size ofthe strut must then comprise the taking of a value at about or below theexperimentally determined maximum stress and shear specifications of thematerial under consideration for use as a strut or column, and thendividing the maximum force to be borne by that value. For aluminum arough figure of about 20000 lb. is known, and using the formulas weobtain 14.7/20000=0.000735. Plugging this intod²=4(0.000735)/π=0.0009358 we obtain 0.031 inches for the diameter ofthis strut made of aluminum. Since this is quite small one would likelyprefer to have an aluminum strut carry more than one square inch of theenclosure surface.

A one quarter inch strut might be preferable. Therefore we divide0.25/0.031=8.0645 or roughly a carrying capacity of eight square inchesof the enclosure surface. Checking we obtain 14.7(8)/20000=0.00588, andd²=4(0.00588)/π=0.07389, giving 0.27 inches for the diameter of thisstrut made of aluminum when carrying eight square inches of theenclosure surface under full evacuation. This is somewhat different fromthe 0.25 inches which we aimed for because it was found convenient touse rounded values for the numbers in the calculations. Thereforerounding error should account for the difference. In any event thenumbers agree closely enough to exemplify how to approximate an accuratesize for the strut or column.

When the enclosure is put into overpressure so that the internalpressure is greater than atmospheric tensile stress should result. Forstruts or columns this is calculated in the same way as compressivestress but with the opposite sign. And it may be preferable that theoverpressure is no more than about two atmospheres.

Also, especially for rigid or semi-rigid enclosures having fixed wallsit is important to avoid the creation of moments. Therefore, in theseembodiments, it is important that the struts and the frame of theenclosure are built to be perpendicular to the enclosure surface. Anydeviation from the ninety degree angle between the frame or columns andthe surfaces of the enclosure will cause a moment to be created, and thegreater the angle the bigger the moment. The effect of the moment is tocreate a twisting force about the neutral axis of the frame or thestrut; this could cause the enclosure to collapse. Therefore care shouldbe taken to construct the frame at right angles to the walls and toconstruct the struts at right angles to the walls. And the sameprinciple applies to all the force generating means; the strut merelybeing the most elementary.

There may also be the problem of direct shear. The experimental valuesfor direct shear will, in general, be different from those for tensileor compressive stress. But the basic formulas may be as shown above.Stress is a complicated phenomenon, but fortunately it has been wellstudied, and for complicated calculations the literature must beconsulted. Direct shear may occur in the enclosures where the walls arebuttressed by the columns or frame. In this case the area will be thecross sectional area of the wall under consideration and we can multiplythe length of the wall by the thickness of the wall to obtain the crosssection. So for a one foot long, three eights inch thick section of wallwe would obtain a cross section of about 0.03125 of a square foot. Ifthe relevant wall surface carries twenty four square inches up to thenext supporting members (struts) then we would have 176.4/.03=5880, or6000 pounds per square foot (rounded) or about one quarter of themaximum safe limit for aluminum (We're only counting one half of thetwenty four square inches because the other half is carried by the nextsupporting members.

And there may also be the problem of bending stresses. This would arisefor enclosures having fixed walls, and would be caused by thecompression or tension that may be experienced by an enclosure wallsection between two supporting struts. The center of the wall sectionshould tend to bend in or out thereby subjecting itself to bendingstress.

For flexible walls and enclosures more complicated calculations may benecessary. However in all cases the cross-section required for theinstant member can be calculated by looking up the maximum value of theselected stress resistance for the material desired and then dividingthe force carried by the instant member by said maximum value. Thisshould give the minimum cross-section required for the instant member toavoid failure. In practice it is of course preferable to not use theminimum cross-section, but rather a cross-section somewhat larger thanthat.

A basic list of force generating means is as follows:

-   -   1. An electric force generating means; this type of means        creates a repulsion or attraction, which may be the result of an        electrostatic force or a magnetic force, generated by        electromagnets or electrostatic plates to push or pull the        flexible walls apart, and thereby creates a vacuum within the        enclosure. An advantage of the electric force generating means        should be that the elements creating the repulsion or attraction        are not in contact with one another after repulsion or        attraction takes place and therefore should not be able to        conduct sound or temperature directly. Alternatively, when        located within or without an enclosure having fixed walls it may        be used to operate a retracting node.    -   2. A hydraulic force generating means; this type of means uses        miniature hydraulic jacks or tubes for creating hydraulic force        to push the flexible walls of an expanding enclosure apart, and        thereby creates a vacuum within the enclosure. Alternatively,        when located in an enclosure with fixed walls it may be used to        operate a retracting node. When located externally it can also        be used to pull the enclosure walls apart by using hydraulic        actuators etc.    -   3. A pneumatic force generating means; this type of means uses        miniature pneumatic jacks or tubes for creating pneumatic force        to push the flexible walls of an enclosure apart, and thereby        creates a vacuum within the enclosure. Alternatively, when        located in an enclosure with fixed walls it may be used to        operate a retracting node. When located externally it can also        be used to pull the enclosure walls apart by using pneumatic        actuators etc.    -   4. A lines force generating means; this type of means uses lines        to pull the flexible walls apart, and thereby creates a vacuum        within the enclosure. It is also used to control and preserve        the orientation of an enclosure and can be used inside an        enclosure to exert inward tension on the enclosure walls.    -   5. A spring force generating means; this type of means uses a        spring to push the flexible walls apart, and to support fixed        walls. Thereby it may create and maintain a vacuum within the        enclosure. When located in an enclosure with fixed walls it may        be used to operate a retracting node. Externally, it can also be        used to pull the enclosure walls apart.    -   6. A lever force generating means; this type of means uses        levers to pull the flexible walls apart, and thereby creates a        vacuum within the enclosure. It generally should be used        externally to the enclosure, although a system of interacting        levers can also be used internally.    -   7. A supporting strut or column force generating means this type        of means uses a strut or column to brace the enclosure walls.        The strut usually should have a preferred acoustic construction        comprising a boundary reflective layer to reduce direct sound        transmission through the strut. However, struts can also be used        externally as bracing to hold the enclosure walls apart.

For more sophisticated results it may be preferable to combine two ormore force generating means to achieve a composite result.

Therefore, according to another of its aspects the invention shouldcomprise a force generating means selected from the group consisting ofan electric force generating means, a hydraulic force generating means,a pneumatic force generating means, a line force generating means, aspring force generating means, a lever force generating means, and astrut force generating means.

In particular the electric force generating means may use anelectrostatic repulsive force or a magnetic repulsive force, generatedby electromagnets or electrostatic plates to push or pull the flexiblewalls apart, and thereby creates a vacuum within the enclosure. But itmay also take the form of a solenoid, an electric actuator, or anelectric motor. An electric force generating means is usually used in anexpanding enclosure having tension and/or compression nodes incombination with flexible plastic, rubber, or aluminum sheeting tocomprise the surface or walls of the enclosure, although any otherflexible sheeting capable of being formed to comprise a hermeticenclosure may be used as well. The electric force generating means maybe used to counteract the internal pressure applied to the enclosurewhen the homogeneous fluid within the enclosure is at greater thanatmospheric pressure due to the action of the pressure varying means. Anadvantage of the electric force generating means should be that theelements creating the repulsive force should not be in contact with oneanother after repulsion takes place and therefore should not be able toconduct sound or temperature directly. Conversely, when the electricforce generating means is used to create an attraction, the attractionmay not be strong enough to create contact between the enclosure wallsso that transmission through the enclosure is not increased by saidattraction. In this case the attraction would normally just besufficient to balance the internal pressure. And the electric forcegenerating means should usually be used just to counteract the externalpressure applied to the enclosure when the homogeneous fluid within theenclosure is rarefied.

In general, an internal electric node will preferably be comprised of asolenoid or an electric actuator. These may be anchored to a nodal base,which is made from a resilient material anchored to the inside of theenclosure wall. When power is applied the resultant electric forcegenerating means may push the enclosure walls apart, thereby creatingthe vacuum. Alternatively, when located inside or outside an enclosurewith fixed walls the electric force generating means may be used tooperate a retracting node and apply whatever stabilizing force isnecessary to maintain the stability of the enclosure. And when theelectric force generating means is used externally, it generally pullsflexible walls apart, although when the power polarity is reversed itcan also be used to push or pull flexible walls together.

The hydraulic force generating means may be comprised of a plurality ofconduits, tubes, or hydraulic lines for the hydraulic liquid. Thehydraulic force can then be applied by placing the hydraulic liquidunder pressure. The hydraulic force generating means may be used tocreate a distending or contracting force on the enclosure wall by meansof internal or external hydraulic lines, or by external hydraulic jacks,or by miniature internal hydraulic jacks, or hydraulic actuators, orhydraulic lines, or hydraulic plates. so that the flexible enclosurewalls could be moved apart, thereby creating said vacuum. A hydraulicforce generating means is usually used with an enclosure having flexiblewalls and tension and/or compression nodes in combination with flexibleplastic, rubber, or aluminum sheeting to comprise the surface or wallsof the enclosure, although any other flexible sheeting capable of beingformed to comprise a hermetic enclosure may be used as well. Varying thedistending or contracting force should vary the degree of distension.The hydraulic force generating means may simply comprise conduits,tubes, or hydraulic lines running along the edges or the surface of theenclosure; these conduits, tubes, or hydraulic lines can then be used todefined the edges and thickness of the enclosure. The conduits, tubes,or hydraulic lines could run along inside or outside the enclosurewalls. When inside the enclosure walls the conduits, tubes, or hydrauliclines should have minimal diffractive and refractive effect on theambient sound. Conversely, when outside the enclosure, the conduits,tubes, or hydraulic lines should have noticeable diffractive andrefractive effects on the ambient sound. And, when located inside oroutside an enclosure with fixed walls the hydraulic force generatingmeans could be used to operate a retracting node.

The pneumatic force generating means may be comprised of a plurality ofconduits, tubes, or pneumatic lines for the pneumatic gas. The pneumaticforce can then be applied by placing the pneumatic gas under pressure.The pneumatic force generating means may be used to create a distendingor contracting force on the enclosure walls by means of internal orexternal lines, or by external pneumatic jacks, or by miniature internalpneumatic jacks, or pneumatic actuators, or pneumatic lines, orpneumatic plates. so that the flexible enclosure walls could be movedapart, thereby creating said vacuum. A pneumatic force generating meansis usually used with an enclosure having flexible walls and/orcompression nodes in combination with flexible plastic, rubber, oraluminum sheeting to comprise the surface or walls of the enclosure,although any other flexible sheeting capable of being formed to comprisea hermetic enclosure may be used as well. Varying the distending orcontracting force should vary the degree of distension. The pneumaticforce generating means may simply comprise conduits, tubes, or pneumaticlines running along the edges or surface of the enclosure; theseconduits, tubes, or pneumatic lines can then be used to defined theedges and thickness of the enclosure. The conduits, tubes, or pneumaticlines could run along inside or outside the enclosure walls. When insidethe enclosure walls the conduits, tubes, or pneumatic lines should haveminimal diffractive and refractive effect on the ambient sound.Conversely, when outside the enclosure, the conduits, tubes, orpneumatic lines should have noticeable diffractive and refractiveeffects on the ambient sound. Therefore, the pneumatic force generatingmeans as well as the hydraulic means may be used to define surfacefeatures or a supplementary surface layer on the enclosure, said surfacefeatures comprised of a secondary enclosure for defining surfaceconvolutions that may be applied to the primary enclosure fordiffractive, refractive, absorptive and reflective effects, in morecomplex embodiments. And, when located inside or outside an enclosurewith fixed walls the pneumatic force generating means could be used tooperate a retracting node.

The line force generating means would normally be used externally to anenclosure having flexible walls. The lines are attached to line nodeswhich may be glued and or laminated to the surface of the enclosure.This would be done in a fashion similar to what has previously beenshown in the camping or sailing arts. To create the vacuum within theenclosure the lines are pulled using a motor or an actuator, ormanually, thus expanding the flexible walls of the enclosure. A lineforce generating means is usually used outside an enclosure havingflexible walls and tension and/or compression nodes in combination withflexible plastic, rubber, or aluminum sheeting to comprise the surfaceor walls of the enclosure, although any other flexible sheeting capableof being formed to comprise a hermetic enclosure may be used as well,The line force generating means would normally be used (although thismay not be necessary in all embodiments) to generate a vertex for aflexible enclosure, thus lending stability to a complicatedconstruction. And it may also be used to simply position the enclosurein the physical space under consideration.

The spring force generating means would normally be used internally withan enclosure having fixed walls. It would be used in a node to maintainthe tension of support for a nodal plate, or to retract a nodal platewhen the opposing force generating means is reduced in power or turnedoff (The opposing force generating means may be defined here as a forcegenerating means that exerts a force opposite to, and lying in a rangevarying from a greater or lesser force than, the force exerted by thespring force generating means. However, the spring force generatingmeans can also be used to support the fixed walls of an enclosure sothat the hermetic properties of the enclosure are retained and tomaintain a nodal means, where the nodal means is comprised of aplurality of nodes having springs. The nodes are distributed within orwithout an enclosure and attached between or without the enclosure wallsthereby maintaining said vacuum within the enclosure. A spring forcegenerating means is usually used in a fixed enclosure having retractingnodes in combination with stiff plastic, aluminum, or glass sheeting tocomprise the surface or walls of the enclosure, although any other stiffsheeting capable of being formed to comprise a hermetic enclosure may beused as well. More generally it would be used in conjunction with arepulsive force generating means, a hydraulic force generating means,and a pneumatic force generating means, to retract a nodal plate whenthese force generating means are turned off.

A leverforce generating means is generally used externally with anenclosure having flexible walls. Usually the lever would be attached toribs forming part of or embedded in the enclosure, or nodes which areglued or laminated to, or on, the enclosure surface. The lever can thenbe moved to pull on the ribs or nodes, thereby expanding the enclosureand creating said vacuum within the enclosure. A lever force generatingmeans is usually used outside a flexible expanding enclosure havingtension and/or compression nodes in combination with flexible plastic,rubber, or aluminum sheeting that comprises the surface or walls of theenclosure, although any other flexible sheeting capable of being formedto comprise a hermetic enclosure may be used as well.

A strut force generating means may also be used, especially with fixedenclosures. But it would generally have acoustic properties. Usually itwould be comprised of a first section having a high absorptioncoefficient for sound and a second section that is highly reflective ofsound by virtue of having an acoustic impedance greater than about tentimes the acoustic impedance of the first section. Additionally thefirst and second sections may be combined to join at an angle of about90 to 30 degrees, or preferably 75 to 45 degrees, or most preferably atabout 60 degrees from the enclosure surface. This should maximize theamount of reflection at the first and second section boundary.

Additionally, for fixed enclosures using sectioned struts, the frame ofthe enclosure should be layered as well with the same materials andangle of joining as was used for the struts. This prevents sound frombeing transmitted around the frame. A strut force generating means isusually used in a fixed enclosure in combination with stiff plastic,aluminum, or glass sheeting to comprise the surface or walls of theenclosure, although any other stiff sheeting capable of being formed tocomprise a hermetic enclosure may be used as well. In addition a fixedenclosure having a strut force generating means may also have anenclosure transduction circuit as described above.

Therefore, according to another of its aspects the invention shouldcomprise a force generating means selected from the group consisting ofa electric force generating means, a hydraulic force generating means, apneumatic force generating means, a line force generating means, aspring force generating means, a lever force generating means, a strutforce generating means, and; wherein the electric force generating meansis creates a distending or contracting force between a first wall and asecond wall, said electric force generating means selected from thegroup consisting of charged plates, an electromagnetic node, a solenoid,an electric actuator, and an electric motor, so that varying theelectric power applied to said charged plates, electromagnetic node,solenoid, electric actuator, and electric motor, causes the distendingor contracting force to vary the degree of distension or contractionbetween a first wall and a second wall,

whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be varied, and;

wherein the hydraulic force generating means creates a distending orcontracting force between a first wall and a second wall, said hydraulicforce generating means selected from the group consisting of a hydraulicconduit, a hydraulic tube, a hydraulic pipe, a hydraulic actuator, and ahydraulic jack,so that varying the hydraulic pressure applied to said hydraulicconduit, hydraulic tube, hydraulic pipe, hydraulic actuator, andhydraulic jack, causes the distending or contracting force to vary thedegree of distension or contraction between said first wall and saidsecond wall,whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be varied, and;wherein the pneumatic force generating means creates a distending orcontracting force between a first wall and a second wall, said pneumaticforce generating means selected from the group consisting of a pneumaticconduit, a pneumatic tube, a pneumatic pipe, a pneumatic actuator, and apneumatic jack,so that varying the pneumatic pressure applied to said pneumaticconduit, pneumatic tube, pneumatic pipe, pneumatic actuator, andpneumatic jack, causes the distending or contracting force to vary thedegree of distension or contraction between said first wall and saidsecond wall,whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be varied, and;wherein the line force generating means creates a distending orcontracting force between a first wall and a second wall, said lineforce generating means comprising a plurality of lines, said pluralityof lines connected to attachment plates on said first wall and saidsecond wall, or on said frame,so that varying the pulling force exerted by said plurality of linescauses the distending or contracting force to vary the degree ofdistension or contraction between said first wall and said second wall,whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be varied, and;wherein the spring force generating means creates a distending orcontracting force between a first wall and a second wall, said springforce generating means comprising a plurality of springs,so that said plurality of springs can absorb said distending orcontracting force to vary the degree of distension or contractionbetween said first wall and said second wall,so that varying the restoring force exerted by said plurality of springscauses the distending or contracting force to reduce the degree ofdistension or contraction between said first wall and said second wall,whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be maintained, and;wherein the lever force generating means creates a distending orcontracting force between a first wall and a second wall, said leverforce generating means comprising a plurality of levers,so that said lever force generating means causes said plurality oflevers to vary the degree of distension or contraction between saidfirst wall and said second wall,so that varying the force exerted by said levers force generating meanscauses the distending force to vary the degree of distension orcontraction between said first wall and said second wall,whereby the volume of said space containing said variable density fluidbetween said first wall and said second wall may be varied.

An electric force generating means may be used with fixed walls andflexible walls. With fixed walls it is usually resident in a node andmay be used to retract or advance a supporting strut. With flexiblewalls it may be located in nodes to cause the enclosure walls toseparate thereby creating said vacuum.

A node may be said to be a restricted loci on the enclosure, having anycombination of three properties; a structural element, a variableelement, and a sensing element. In practice, a force generating meansmay preferably be applied at a node of the enclosure. Supporting strutsare really representative of the most primitive form of force generatingmeans; that is to say support of a purely static nature. For betterresults it is preferable that a dynamic force generating means be used.For enclosures having fixed walls it may therefore be preferable thatthey also have retracting nodes. A retracting node is usually comprisedof a force generating means dynamically functioning as a retractablesupporting strut. Usually a distal end of the force generating meanscomprises a nodal pad that normally rests evenly against a nodal plateattached to the enclosure wall, but that is pulled away from theenclosure under retraction.

Clearly, for an enclosure having fixed walls, if the walls weresupported entirely by retracting nodes and all nodes retractedsimultaneously, structural failure might result. Therefore the enclosuremay be constructed to comprise more retracting nodes than would benecessary to maintain structural stability, The excess retracting nodesmay then be retracted without causing structural failure. The advantageconferred by this embodiment is that the sound transmission may beincreased or decreased across different areas of the enclosure therebyallowing the sound baffling characteristics of the enclosure to bemodulated.

Some simple arrangement which may comprise a retracting node areretracting springs (a spring force generating means) which would retractthe nodal pads, but are prevented from doing so because a pneumaticforce generating means, or a hydraulic force generating means, or anelectric force generating means, or any other force generating meansmaintain the retracting node in the extended position. In practice itwould usually be preferable to use a pneumatic force generating means,because usually a line from the pressure varying means will be attachedto the enclosure and will be able to provide the requisite air supplyand pressure to the pneumatic force generating means. It should be notedthat when a large number of nodes as discussed here are being used, theyeffectively function as a nodal means.

It may also be advantageous to add a nodal means for use with anelectric force generating means to the enclosure. This involves thecreation of nodes at useful locations within the enclosure, along thesurface of the enclosure or around the perimeter of the enclosure.Alternatively, one could say that nodes may be located in the interiorof the enclosure usually in tandem with, or in lieu of, a structuralsupport, along faces of the enclosure, along edges of the enclosure, andalong vertices of the enclosure. In one sense, then, a node is merely alocation within or on the structure of the enclosure, although itusually also functions as a location for a structural element, or avariable element, or a sensing element. And the walls of the enclosuremay be reinforced to allow the placement of these elements.Alternatively the nodes may be loci for attaching force generating meansto the enclosure.

In general a force generating means should be applied at a node althoughthis may not always be the case, The node should generally be given thename of the force generating means, a strut force generating means beingapplied at a strut node, a hydraulic force generating means beingapplied at a hydraulic node etc.

The question remains whether the node is internal or external, Internalnodes reside inside the enclosure while external nodes may be attachedto a crib surrounding the enclosure or they may be directly attached toa wall or a structural component (e.g. a pillar) of the physical spaceunder consideration, or just to the enclosure surface.

Lastly, the nodes may be of two general types, retracting nodes andtension and/or compression nodes. The retracting nodes are used withfixed walls that are substantially able to withstand the internal orexternal pressure on their own. For an enclosure containing retractingnodes a substantial number of the nodes will not be necessary tomaintain structural integrity at any one time. Consequently, by changingthe configuration of the nodes that are in the retracting vs. supportingstates the transmission of sound or heat can be preferably shifted fromone part of the enclosure to another.

It may therefore be preferable that according to another one of itsaspects the invention comprises; an enclosure further comprising a node,said node limited to a loci on said enclosure, said node furthercomprising at least one of a structural element, a variable element, anda sensing element.

The nodes may roughly be divided into retracting and tension and/orcompression nodes and may often be evenly distributed within theenclosure or across the enclosure surface. And, since the nodesgenerally are loci for variable elements, it is possible to use thecontrolling means to control or activate them independently or assubsets of the total number of nodes in the enclosure. This could allowthe transmission of sound and/or thermal energy to be varied across asurface of the enclosure. Those areas of the surface where the nodepermitted the transmission of sound and/or thermal energy would betransmitting sound and/or thermal energy, whereas areas where the nodedid not allow the transmission of sound and/or thermal energy would bebarred from transmitting sound and/or thermal energy.

It may be preferable to control a nodal means through the output from aPROM nodal chip or a standard chip that is capable of serving as a nodalchip and handling the specific electronic problem to suit.

The nodal chip essentially controls the activation of the nodes topreferred state and will have one output for each of the nodes in theenclosure. Therefore the nodal chip can switch any permutation of nodesinto the preferred state (e.g. retracted or extended), thereby allowingthe corresponding nodes to be controlled.

On the input side the nodal chip will have the ability to receive asignal from the controlling means and to convert that signal into adigital representation presented on the nodal chip output leads, ascomprising either triggering voltages for the active elements orcomprising neutral voltages that are insufficient to trigger the activeelements (e.g. switch on an electric motor). Therefore, the output leadswill be configured as preferable for a particular application. For anelectric motor, on lead would signal the on/off condition. But otherleads might indicate how far to turn (for a stepper motor). Therefore asingle chip may not always suffice and an electronic nodal circuit mayhave to be constructed so that the appropriate number of output leads ismade available to control the nodes, as required.

Tension and/or compression nodes are used in combination with flexiblewalls. Flexible walls will be put under compression if the externalpressure is greater than the internal pressure. Flexible walls will beput under distension if the internal pressure is greater than theexternal pressure. When a flexile wall of an enclosure is in a state ofcompression the internal tension and/or compression nodes will be in astate of compression while the external tension and/or compression nodeswill be in a state of tension. When a flexible wall enclosure is in astate of tension, the internal tension and/or compression nodes will bein a state of tension and the external tension and/or compression nodeswill be in a state of compression.

The tension and/or compression nodes may therefore be able to adjust tothe internal pressure of an enclosure having flexible walls. Incombination with a pressure varying means they need to change the amountand direction of the force applied by the force generation means as maybe required to compensate for any change in the internal pressure of theflexible enclosure.

It may therefore be preferable that according to one of its aspects theinvention further comprises; an enclosure further comprising a nodalmeans having a plurality of retracting node variable elements or aplurality of tension and/or compression node variable elements, saidnodal means further comprising a controlling means, so that saidcontrolling means selectively enables the transmission of sound or heatthrough a subset of said plurality of retracting node variable elementsor said plurality of tension and/or compression node variable elements,whereby the transmission of sound or heat may be varied over a region ofsaid enclosure.

And it may further be preferable that according to one of its aspectsthe invention embodies a nodal means in combination with a controllingmeans, so that said controlling means controls the nodes of said nodalmeans, and the geometrical properties of said enclosure, or the acousticproperties of said enclosure, or the thermal properties of saidenclosure are optimized.

And it may further be preferable that according to one of its aspectsthe invention further comprises an enclosure having fixed walls incombination with a plurality of retracting nodes or an enclosure havingflexible walls in combination with a plurality of tension and/orcompression nodes.

In conjunction with the enclosure having a force generating means and anodal means it may also be preferable to have a pressure varying means.The pressure varying means contains a means for admitting and removing,and, in addition also has a compressor for increasing the pressuresabove atmospheric. This means that the pressure varying means canincrease the pressures above the ambient pressure and decrease thepressures below ambient pressure. This may be useful in certain acousticapplications. There are certain refractive effects that become morepronounced when the enclosures are at a greater pressure. For example,an acoustic lens may use a higher pressure than atmospheric to obtain arefractive focus for sound.

It may therefore be preferable that according to another of its aspectsthe invention further comprises; a pressure varying means (756)connected to said enclosure, so that by admitting and removing matter toand from said enclosure the sound and thermal baffling characteristicsof said enclosure are varied by said pressure varying means. But thepressure varying means also contains additional elements and functionsbeyond those shown by the means for admitting and removing.

The means for admitting and removing is contained within the pressurevarying means (756) and should have a sealed piping network (335, 336,338, 340, 342) to enable the admitting and removing of matter to andfrom the enclosures. The piping network may have a separate valve (294,296) for each pipe leading from the means for admitting and removing toeach enclosure. The means for admitting and removing should also havecontrolling lines (344, 346, 348, 350, 352) for setting the valves aswell as a vacuum pump connected to the pipes by means of the valves.Upon receiving the appropriate instructions the valve leading to anenclosure where matter is to be admitted and removed is opened or closedto a degree determined by the instructions. Then matter is removedthrough the action of the vacuum pump if required. Or matter may beadmitted by means of the external pressure, if that is what is required.The external pressure may force air into the enclosures directly throughan intake valve contained in the means for admitting and removing. Thisintake valve may also function as an exhaust valve for the vacuum pump.The means for admitting and removing may therefore also contain anapparatus for enabling either the vacuum pump or the external pressureto act on the piping network by means of this intake or exhaust valve.Alternatively, the matter may be retained within the means for admittingand removing. This implies that a storage chamber for storing matter iscontained within the means for admitting and removing. The storagechamber (758) is capable of storing all the matter that is presentwithin the enclosures, the piping network, the vacuum chamber, and thevacuum pump. Matter may therefore be removed from the enclosures andstored in the storage chamber which may be a vacuum capacitor by themeans for admitting and removing. Or some of the same matter may beadmitted to the enclosures by the means for admitting and removing. Theimplementation of either admitting or removing is carried out on thebasis of information received from the means for measuring.

The pressure varying means also has a piping network (770, 772, 774,776, 778) to enable the pressurizing or decompression and evacuation ofthe enclosures. And the piping network may also have at least oneseparate valve (751, 782, 784, 786), associated with each pipe and/orenclosure (788, 790, 792). Also the pressure varying means will havecontrolling lines for setting the valves as well as a compressor forincreasing the pressure above atmospheric.

The pressure varying means may also have matter density reservoirs(750), which may have the same physical construction as a vacuumcapacitor, and that contain homogeneous fluid matter of varying densityfor admittance to the enclosure as may be preferable. The densities willbe different from the density of the atmosphere and function to changethe refractive index of sound at the enclosure wall and the homogeneousfluid matter boundary. This should have novel results with regards tothe focusing of sound, or the refraction and reflection of sound ingeneral.

It may therefore be preferable that according to one of its aspects theinvention further comprises; a pressure varying means having a pluralityof matter density reservoirs, said matter density reservoirs comprisinghomogeneous fluid matter having different densities, so that the densityof matter within said enclosure may be varied from the density of theatmosphere by said pressure varying means.

When a matter density reservoir is used in operation, the homogeneousfluid matter may be kept separate from the atmosphere to substantiallypreserve its purity. This is accomplished by reserving a conduit paththrough the piping network for the use of the homogeneous fluid matter.Alternatively the homogeneous fluid matter may be mixed with theatmosphere to achieve a preferred mixture having a different density.This mixture is then stored in a mixing chamber which may be part of avacuum capacitor. Or two or more homogeneous fluid matters may be mixedtogether to comprise a preferred mixture having a different densitywithin a mixing chamber. The preferred mixture having a differentdensity may then be admitted to the enclosure from the mixing chamber.Obviously, fluids known to be hazardous to human health must not be usedin an environment where humans are active.

Therefore according to another of its aspects the invention furthercomprises; a mixing chamber (752), for mixing said homogeneous fluidmatter having different densities, so that the density of matter withinsaid enclosure may be varied by said pressure varying means.

If the measured values and characteristics of the ambient sound do nothave a sufficiently close correspondence to the input parametric valuesand characteristics of the ambient sound then matter is either admittedor removed to increase this correspondence. Then, after the admitting orremoving of matter has been carried out by the means for admitting andremoving, new measurements of the values and characteristics of theambient sound in the physical space controlled by said sound bafflingdevice are taken. These new measured values and characteristics of theambient sound are then correlated by the means for correlating to thestored parametric values and characteristics of the ambient sound and,if the new correspondence lies within a parametrically set degree ofaccuracy, the procedure of adjusting the sound baffling characteristicsof the sound baffling device is halted.

Alternatively, if the new measured values and characteristics of theambient sound do not have a sufficiently close correspondence to thestored parametric values and characteristics of the ambient sound, theprocedure is repeated. The controlling means therefore has a feedbackmechanism implemented by the means for correlating which carries outadjustments based on the measured values and characteristics of theambient sound until the stored parametric values and characteristics ofthe ambient sound and the measured values and characteristics of theambient sound agree within an input parametric level of accuracy set bythe input means. When such agreement is reached the means forcorrelating enters a sampling loop that checks periodically to ensurethat the agreement of the measured values and characteristics with thestored parametric values and characteristics of the ambient soundcontinues. Should the agreement be lost the adjustment of the soundbaffling characteristics of the sound baffling device should resume.

The controlling program may carry out the actual correlation anddetermination of values. Basically three sets of variables may be usedas well as one set of constants or operating principles. The first setof variables is just the set of input parametric values andcharacteristics (302) of the ambient sound input by the operator or userof the sound baffling device. The second set of variables, which mayalso be input by the user, simply lists the input tolerances (303)required for each of the values and characteristics of the ambient soundbefore the convergence procedure carried out by the controlling meansmay be terminated. The last set of variables lists the actual newmeasured values and characteristics (312) of the ambient sound as of thelast reading of the sensors.

The means for correlating will have default settings for the first andsecond set of variables, namely the default parametric values andcharacteristics and the default tolerances (754,756). This may ensurethat, if the controlling means is engaged and no input parametric valuesand characteristics of the ambient sound or input tolerances are enteredthrough the input means, the sound baffling device will still functionin a useful way. When a controlling program is used, the set ofconstants and operating principles contained within the controllingprogram should act on the data received by the sensors with reference tothe default parametric values and characteristics of the means forcorrelating, or the input parametric values and characteristics of theinput means.

These constants and operating principles are essentially drawn from thescience and technology of acoustics and the science and technology ofthermal control. The spatial configuration of the sound baffling deviceis evaluated scientifically and the relevant data is entered into thecontrolling program as a list of constants. Specifically the datacomprises a description of the physical space to be controlled, thenumber of enclosures used, and the shape, disposition and size of theenclosures as well as the formulation of interaction among theseentities.

The operating principles are drawn from the science and technology ofacoustics and the science and technology of thermal control, and arestored in the controlling program. They are comprised of the equationsof acoustics and thermal science as well as algorithms using theseequations to calculate and predict an acoustic or thermal result. In theapplication of these equations and algorithms, the constants drawn fromthe specific case data are substituted by the controlling program forthe appropriate variables in the equations and algorithms. The equationsand algorithms may then be used to create predicted parametric valuesand characteristics of the ambient sound in the controlled physicalspace under consideration for a given state of the sound bafflingdevice.

The controlling program then compares the predicted parametric valuesand characteristics of the ambient sound with the input parametricvalues and characteristics of the ambient sound read into the programfrom the input means. By means of the equations and algorithms thecontrolling program then estimates the change in the state of the soundbaffling device required to create the parametric values andcharacteristics of the ambient sound within the physical space underconsideration governed by the sound baffling device. Having estimatedthe necessary change, the controlling program then sends a requisitelist of instructions through the means for correlating to the means foradmitting and removing which, by admitting or removing matter in therequired amounts to and from the various enclosures changes the state ofthe sound baffling device.

The controlling program then checks the measured values andcharacteristics of the ambient sound to see if they now lie within theallowed stored parametric tolerance. If the measured values andcharacteristics of the ambient sound lie within the stored parametrictolerance, the controlling program next enters a sampling loop. In theloop it samples the measured values and characteristics of the ambientsound and the input parametric values and characteristics of the ambientsound at a preset parametric rate. If a difference in the measuredvalues and characteristics of the ambient sound falling outside thestored parametric tolerance is found by sampling, then a new set ofinstructions is sent to the means for admitting and removing and/or thepressure varying means, so that this difference may be reduced to fallwithin the stored parametric tolerance. In this fashion the controllingmeans converges automatically to establish an optimum correlation to thepreferred set of parametric values and characteristics of the ambientsound in the physical space governed by the sound baffling device. Butthe optimum correlation may not be a total correlation. If after apreset number of trials, one or more of the preferred set of parametricvalues and characteristics still falls outside the stored parametrictolerance, the convergence procedure may, at least temporarily, beaborted with respect to the offending stored parametric values andcharacteristics. This may be done by simply removing the parametricvalues and characteristics in question for a determined number ofiterations from the total list of values and characteristics, which mustbe considered by the controlling means.

For embodiments that function without the optional controlling programand microprocessor, some tasks normally handled by these elements may beassumed by the operator. And the controlling means may also haveadditional on board hardware for dealing with some of these tasks. Thismay involve the use of additional circuitry and/or the use ofprogrammable logic devices.

To speed up the removal of matter from the enclosures, it may be founduseful to maintain an appropriately sized vacuum chamber in an evacuatedstate. As shown in a still further part of FIG. 13, the vacuum chamberis also connected to the enclosures through the valves and the pipingnetwork. When the valves between the enclosures and the vacuum chamberare opened, the matter rushes from the enclosures into the vacuumchamber, thereby causing the enclosures to be evacuated at a high speed.This allows the matter within the enclosures to be adjusted morerapidly. It may therefore be preferable that the invention furthercomprises a large vacuum chamber (316) connected by chamber valves (318,320) to said sound baffling device, said vacuum chamber maintained in astate of vacuum by means of a removal valve (322) and pipe (335)connecting said vacuum chamber to said means for admitting and removing,so that when said controlling means causes said chamber valves to open,pressurized matter present within said enclosures flows rapidly intosaid vacuum chamber, so that the speed with which the matter within saidenclosures is removed is optimized.

However, for those embodiments of the invention where the enclosures donot permit the admitting and removing of matter, the creation of thevacuum inside the enclosures may be most easily done in a vacuumchamber. This process of manufacture may be carried out by means ofrobotics. Or it could be performed by appropriately equipped men.Accordingly, it is preferable that the step in the process ofmanufacture which creates said enclosure is carried out within a vacuumchamber, so that the vacuum within said vacuum chamber is incorporatedinto said enclosure.

A more concise and specific aspect of the operation of the preferredembodiment is shown in the program logic depicted by the flowchart ofFIG. 39. The flowchart begins with START (700) which is merelyrepresentative of switching the device on. Start also assumes that onlya means for correlating is being used so that there is just onecalculating means; therefore N the count of calculating means is set toone, N=1. Next (702), the logic checks to see if input parametric valuesand characteristics have been entered into the input means; if yes (704)the stored values and characteristics are set equal to the inputparametric values and characteristics, if no (706) the stored parametricvalues and characteristics are set equal to the default parameters andcharacteristics. Next (708) the logic checks to see if input toleranceshave been entered. If yes (710)) the stored tolerances are set equal tothe input tolerances and, if no (712)) the stored tolerances are setequal to the default tolerances.

Next (714) the measured values and characteristics are taken inmeasurement from the physical space under consideration. And afterchecking to see that N=1 the logic determines a bench mark (716) bycomparing the measured values and characteristics to the storedparametric values and characteristics. The benchmark in a general sensecomprises the difference between the stored values and characteristicsand the measured values and characteristics. The benchmark would alsocomprise a value indication of the amount of adjustment which thepressure varying means should make in combination with the forcegenerating means as well as adjustments to variable elements etc.; sothat the benchmark may comprise an adjustment value indication for theforce generating means and the pressure varying means, including andadjustment value indication for the means for correlating which wouldhandle the adjustment of variable elements. The logic next (718) checksto see if the benchmark falls within the range of values given by thestored tolerances. If yes (720) the logic waits for an intervalpredetermined by the requisite stored parametric tolerance and then getsa new measurement (714) of the measured values and characteristics fromthe physical space under consideration, re-calculates the benchmark(716) and checks (718) to see if the benchmark still falls within therange of values given by the stored tolerances.

When the benchmark falls outside the range of values given by the storedparametric tolerances the logic checks (722) to see if the controllingmeans also comprises a microprocessor. If yes (724), a second benchmarkis calculated by the microprocessor using comparison. The logic next(726) checks to see if the second benchmark falls within the range ofvalues given by the stored parametric tolerances. If yes (728), N is setequal to 2, and the logic waits for the requisite interval and then getsa new measurement (714) of the measured values and characteristics fromthe physical space under consideration, and, if N=2, is sent immediatelyto re-calculate the second benchmark (724) and check (726) to see if thesecond benchmark still falls within the range of values given by thestored parametric tolerances. If yes, after waiting for the requisiteinterval the cycle is repeated; if no (730), the logic checks to see ifthe controlling means also comprises a neural net. If yes (732), a thirdbenchmark is calculated by the neural net using comparison. The logicnext (734) checks to see if the third benchmark falls within the rangeof values given by the stored tolerances. If yes (736), N is set equalto 3, and the logic waits for the requisite interval and then gets a newmeasurement (714) of the measured values and characteristics from thephysical space under consideration, and if N=3, is sent immediately tore-calculate the third benchmark (732), and check (734) to see if thethird benchmark still falls within the range of values given by thestored parametric tolerances. If yes, the cycle is repeated; if no(734), the force generating means and/or the pressure varying means(726) is adjusted to change the state of the physical space underconsideration.

If new information is input into the input means during the operation ofthis program, the program will be halted, and then resume at START assoon as the input operation is completed, Also an error condition mightarise and cause N to have a value other than one, two, or three. Thiswould also cause the program to halt. It should be noted that this ismerely one way in which the calculating means or nodes could beorganized, Alternatively they could be organized to operateconcurrently.

An enclosure having flexible walls may also comprise a force generatingmeans in combination with a pressure varying means. The pressure varyingmeans is used to pressurize and depressurize the enclosure and the forcegenerating means is used to balance this expansion or contraction. Orthe pressure varying means is used to remove matter from the enclosurethereby causing the enclosure to contract and a force generating meansis used to anchor the exterior of the enclosure to prevent collapse atpreferred loci on the enclosure surface.

It may therefore be preferable that according to one of its aspects theinvention further comprises; an enclosure, wherein said enclosure has asurface comprised of a flexible wall, and; the shape of said surface isdetermined by said pressure varying means operating in combination withsaid force generating means.

A preferred shape for the surface of the enclosure would be a circularshape having a substantially convex or concave side. An enclosure shapedin this fashion should function as an acoustic lens. If both sides ofthe enclosure were convex and the speed of sound inside the lens weregreater than the speed of sound outside the lens then the direct soundwave would diverge from the acoustic lens after passing through theacoustic lens. If both sides of the enclosure were concave then thedirect sound wave would be focused, and converge to a focal point.Alternatively, if the speed of sound inside the lens were less than thespeed of sound outside the lens then for said convex and concaveacoustic lens constructions the direct sound wave would be focused anddiverging from the acoustic lens, respectively.

Therefore according to another of its aspects the invention furthercomprises; an enclosure having a surface comprising an annular shapehaving a substantially convex or concave side, so that said enclosurefunctions as an acoustic lens.

Carrying this notion one step further, one can create an enclosurecovered with a plurality of surface enclosures, whose shape and sizeroughly corresponds to the surface features of the enclosure (e.g. For acube you would have six surface enclosures.).The transmission of energythrough each of the surface enclosure may then be controlled by thepressure varying means operating in combination with a force generatingmeans, so that a predetermined amount of energy may be transmittedthrough said enclosure.

Therefore according to another of its aspects the invention has anenclosure further comprising a plurality of surface enclosures, saidsurface enclosures comprising a substantially contiguous covering of thesurface of said enclosure, said surface enclosures further comprisingsaid pressure varying means and said force generating means, so that thetransmission of sound through said surface enclosures may be varied bysaid pressure varying means operating in combination with said forcegenerating means, so that said enclosure is effective to achieve apredetermined distribution of sound.

And it may be preferable to place a sound generating means inside theenclosure. The surface enclosures then control the transmission of soundout of the enclosure. If all the surface enclosures are madenon-transmitting for sound, then the transmission of sound from thesound generating means within the enclosure should substantially bestopped. Alternatively, is some of the surface enclosure are capable ofthe transmission of sound then the transmission of sound will take placethrough those surface enclosure thereby enabling the selectivedirectional transmission of sound.

It may therefore be preferable that according to one of its aspects theinvention further comprises; an enclosure containing a sound generatingmeans, said sound generating means contained within said surface of saidsurface enclosure, and;

wherein said plurality of surface enclosure enable directional controlover the transmission of sound from said sound generating means,

so that said sound generating means is effective to operate as adirectional sound source.

Or, it may be preferable that according to one of its aspects theinvention further comprises; an enclosure further comprising a soundgenerating means, said sound generating means contained within saidenclosure, and;

Said enclosure further having a plurality of surface enclosures, so thatsaid plurality of surface enclosures enable directional control over thetransmission of sound from said sound generating means, whereby saidenclosure is effective to operate as a directional and variable soundsource.

EXAMPLES Example 1 (Pneumatic Force Generating Means-Flexible Wall)

Using a mold for preparing a rubber or plastic product, hermeticallyform an annular pneumatic tube made of rubber or plastic or othermoldable hermetic material, said annular pneumatic tube molded in onepiece with a rear wall and; said annular pneumatic tube further having acentral groove and a first set of mutually parallel pneumaticcross-linking tubes attached to the annular pneumatic tube between therear wall and the central groove and further having a second set ofmutually parallel pneumatic cross-linking tubes attached to the annularpneumatic tube between the front wall and the central groove and runningperpendicularly to said first set of parallel pneumatic cross-linkingtubes.

The annular pneumatic tube may be made of rubber or plastic or any othermoldable hermetic material, and may also have openings for accepting theplacement of an external and internal valve located in the outside layerand the inside layer of the annular pneumatic tube, respectively. Thisis only necessary when the connection of a pressure varying means to thetube is contemplated and embodiments that do not use a pressure varyingmeans would not need these openings.

After releasing the annular pneumatic tube from the mold and testing thehermetic properties of the tube, attach an internal frame by fitting theinternal frame into the central groove. The internal frame will havetube frame holders for attaching to the central groove and nodal platesfor attaching to the sets of parallel pneumatic cross-linking tubes.Next add attachment plates to the outside wall of the annular pneumatictube, if required. The internal frame and the attachment plates may bemade of metal or any other material capable of being attached to theannular pneumatic tube so that the handling of forces upwards of onehundred pounds is enabled.

Next attach a hermetic pipe valve to the outside layer and optionallyattach a hermetic pipe insert valve to the inside layer of the annularpneumatic tube so that these valves are suitable for connection to apressure varying means and a means for admitting and removing. Thehermetic pipe valve is connected to the pressure varying means and inparticular to the high pressure output which is used to increase thepressure in the annular pneumatic tube to above atmospheric. Thehermetic pipe insert valve may be connected by the pipe insert to thepressure varying means to enable both the increasing of the pressure inthe enclosure to above atmospheric or the reduction of the pressure inthe enclosure to below atmospheric.

The pipe insert is a smaller pipe optionally contained in the pipe andmay be connected to the hermetic pipe insert valve in the annularpneumatic tube so that a pressure varying means may act on the interiorof the enclosure.

Next, increase the pressure in the pneumatic tube so that the tubeachieves substantially its maximum rated expansion and acts like theopen frame of an enclosure having the shape of a hollow sheet. Apply andhermetically seal a front wall to the open side of the annular pneumatictube.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

The operation of this embodiment is governed by the pneumatic forcegenerating means. Starting with atmospheric pressure in the enclosure;when the enclosure is blown up to expand to ten times its size theatmospheric pressure inside the enclosure will be one tenth atmospheric,assuming the hermetic properties are not compromised. The basicoperating principle is that over pressure at the surface of theenclosure can be balanced by increasing the pressure in the pneumatictubes.

(Of course the pneumatic tube need not be made in one piece. In fact thepneumatic tube having a central groove and the parallel pneumaticcross-linking tubes can be made separately and then put together. Boththe rear wall and the front wall can be produced separately and thenattached to the annular pneumatic tube having a central groove.)

The attachment plates will have eyes or other attaching means for, mostusually attaching to a line force generating means. The line forcegenerating means will then be able to position the enclosure in thephysical space or it may exert forces to effect changes in the shape ofthe enclosure. These forces should be kept sufficiently small so thatthe hermetic properties of the enclosure are not compromised.

Example 1A (Example 1 with a Spring Force Generating Means Added)

Create an enclosure as defined in example 1, but add a spring forcegenerating means as follows. Firstly, along the inside of the rear andfront wall create nodal plates occupying geometrically regular positionsin the open portions of the grid created by the first and second set ofpneumatic cross-linking tubes. Next, before adding the front wall,attach the rear part of the springs to the nodal plates located in therear wall. Lastly, when attaching the front wall attach the front partof the springs to the nodal plates in the front wall prior tohermetically attaching the front wall to the annular pneumatic tube.

The springs are tensioned to exert substantially no force on theenclosure when the interior is at less than atmospheric. But when thepressure varying means is used to increase the pressure in the enclosureabove atmospheric the springs exert a contracting force on the enclosurewalls, thereby preventing excessive expansion of the enclosure.

It may also be preferable that the spring is contained in twocylindrical halves. One half cylinder will fit inside the other and theends of both half cylinders are closed off. The spring is connected tothe end plates in the ends of both half cylinders. And when assembledthe spring should create a slight tension holding the halves together.

Should the enclosure wall move apart during operation the tension willbecome more pronounced and the spring nodal means will exert acontracting force to bring the enclosure walls closer together.

Example 2 (Hydraulic Force Generating Means—Flexible Wall)

Using a mold for preparing a rubber or plastic product, hermeticallyform an annular hydraulic tube made of rubber or plastic or othermoldable hermetic material, said annular hydraulic tube molded in onepiece with a rear wall and; said annular hydraulic tube further having acentral groove and a first set of mutually parallel hydrauliccross-linking tubes attached to the annular hydraulic tube between therear wall and the central groove and further having a second set ofmutually parallel hydraulic cross-linking tubes attached to the annularhydraulic tube between the front wall and the central groove and runningperpendicularly to said first set of parallel hydraulic cross-linkingtubes.

The annular hydraulic tube may be made of rubber or plastic or othermoldable hermetic material, and may also have openings for accepting theplacement of an external and internal valve located in the outside layerand the inside layer of the annular hydraulic tube, respectively. Thisis only necessary when the connection of a pressure varying means to thetube is contemplated and embodiments that do not use a pressure varyingmeans would not have these openings.

After releasing the annular hydraulic tube from the mold and testing thehermetic properties of the tube, attach an internal frame by fitting theinternal frame into the central groove. The internal frame will havetube frame holders for attaching to the central groove and nodal platesfor attaching to the sets of parallel hydraulic cross-linking tubes.Next add attachment plates to the outside wall of the annular hydraulictube, if required. The internal frame and the attachment plates may bemade of metal or any other material capable of being attached to theannular hydraulic tube so that the handling of forces upwards of onehundred pounds is enabled.

Next attach a hydraulic pipe valve to the outside layer and connect itto a hydraulic reservoir. And attach a hermetic pipe insert valve to theinside layer of the annular hydraulic tube so that this valve issuitable for connection to a pressure varying means and a means foradmitting and removing. The hydraulic pipe valve is connected to thehydraulic reservoir and when the hydraulic pressure is increased theresulting hydraulic force can counteract the exterior pressure whichincreases as the degree of evacuation in the enclosure rises.

The hermetic pipe insert valve may be connected by the pipe insert tothe pressure varying means to enable both the increasing of the pressurein the enclosure to above atmospheric or the reduction of the pressurein the enclosure to below atmospheric. The pipe insert is a smaller pipecontained in the pipe and is connected to the hermetic pipe insert valvein the annular hydraulic tube so that a pressure varying means may acton the interior of the enclosure.

Next, increase the pressure in the hydraulic tube so that the tubeachieves substantially its maximum rated expansion and acts like theopen frame of an enclosure having the shape of a hollow sheet. Apply andhermetically seal a front wall to the open side of the annular hydraulictube.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

The operation of this embodiment is governed by the hydraulic forcegenerating means. Starting with atmospheric pressure in the enclosure;when the enclosure is increased in size the atmospheric pressure insidethe enclosure will be reduced, assuming the hermetic properties are notcompromised. The basic operating principle is that over pressure at thesurface of the enclosure can be balanced by increasing the pressure inthe hydraulic tubes.

(Of course the hydraulic tube need not be made in one piece. In fact thehydraulic tube having a central groove and the parallel hydrauliccross-linking tubes can be made separately and then put together. Boththe rear wall and the front wall can be produced separately and thenattached to the hydraulic tube having a central groove.)

The attachment plates will have eyes or other attaching means for, mostusually attaching to a line force generating means. The line forcegenerating means will then be able to position the enclosure in thephysical space or it may exert forces to effect changes in the shape ofthe enclosure. These forces should be kept sufficiently small so thatthe hermetic properties of the enclosure are not compromised.

Example 2A (Example 2 Connected to an Electric Force GeneratingMeans—Flexible Wall)

Create an enclosure as defined in example 2, but add an electric forcegenerating means as follows. Firstly, along the inside of the rear andfront wall create nodal plates occupying geometrically regular positionsin the open portions of the grid created by the first and second set ofmutually parallel hydraulic cross-linking tubes. Next, before adding thefront wall, attach small solenoids to the nodal plates located in therear wall. Lastly, when attaching the front wall attach the solenoidplunger to the nodal plates in the front wall prior to hermeticallyattaching the front wall to the annular hydraulic tube.

The solenoids are tensioned to exert substantially no force on theenclosure when the interior is at less than atmospheric. But when thepressure varying means is used to increase the pressure in the enclosureabove atmospheric the solenoids spring into action and exert acontracting force on the enclosure walls, thereby preventing excessiveexpansion of the enclosure.

It may also be preferable that the solenoid is contained in twocylindrical halves. One half cylinder will fit inside the other and theends of both half cylinders are closed off. The solenoid is connected tothe end plate of the cylinder that is attached to a nodal plate locatedin the rear wall. The solenoid plunger in the expanded position isconnected to the end plate of the cylinder attached to a nodal platelocated in the front wall. When a distending force is applied to theenclosure walls (e.g. by the pressure varying means) a pressure switchin the solenoid may activate the solenoid so that the solenoid willexert a contracting force to bring the enclosure walls closer together.

Example 2B (Hydraulic Force Generating Means—Fixed Wall)

Prepare a frame having three to five millimeters thickness. Hermeticallyattach a back plate or wall to this frame, preferably made from amaterial having at least one tenth the acoustic impedance of the framematerial. The attachment may be made by means of an attachment framethat fits over the back plate and hermetically seals it against theframe. The attachment frame may be made of either the frame material orthe back plate material. And the frame and the attachment frame may bemade of metal or any other material capable of the handling of forcesupwards of one hundred pounds.

The frame should also have openings for accepting the placement of apneumatic and a hydraulic valve. Add the hydraulic valve to allow theadmission of hydraulic fluid from a hydraulic reservoir and add thepneumatic valve to allow the enclosure to be connected to a pressurevarying means.

Next attach a hydraulic line to the hydraulic valve and connect it tothe hydraulic reservoir. And attach a pneumatic line to the pneumaticvalve and establish a connection to a pressure varying means and a meansfor admitting and removing. The pneumatic line is connected to thepressure varying means to enable the pressure in the enclosure to bevaried from atmospheric.

Next, attach a hydraulic tube to the back plate by gluing, so that thetube describes a geometrically uniform pattern over the entire backplate. More than one tube could be used to comprise the geometricallyuniform pattern, but it may be convenient to use only one tube. Thegeometrically uniform pattern could be a repetitive pattern ofsinusoidal or serpentine curves, or any other geometrically uniformpattern. And after the hydraulic tube has been attached to the backplate the front plate is fitted over the hydraulic tube and hermeticallyattached to the frame. The attachment may be made by means of anattachment frame that fits over the front plate and hermetically sealsit against the frame. The attachment frame may be made of either theframe material or the front plate material. And the frame and theattachment frame may be made of metal or any other material capable ofthe handling of forces upwards of one hundred pounds.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pneumatic line into the enclosure. But it may bepreferable to have the sensor operate by using RF technology to transmitand receive the requisite information as necessary.

The operation of this embodiment is governed by the hydraulic forcegenerating means. Starting with atmospheric pressure in the enclosure;when the atmospheric pressure inside the enclosure is reduced by thepressure varying means, assuming the hermetic properties are notcompromised, the hydraulic pressure can be increased therebycounteracting the effects of the external pressure. The basic operatingprinciple is that over pressure at the surface of the enclosure can bebalanced by increasing the pressure in the hydraulic tubes.

Example 2C (Example 2B Further Comprising a Line Force Generating Means)

In finishing the enclosure of Example 2C, prior to attaching the frontand back plates finely machine line grooves into the outside faces ofthe front and back plate. Also finely machine the line grooves into theenclosure frame and the attachment frame so that the line grooves of theframe, attachment frame and front and back plates will line up tocomprise a continuous groove on assembly.

After assembly attach a bridge to the frame of the enclosure. The bridgeshould have a ratchet (driven by an electric motor for automaticoperation) and should also have eyes for holding the lines. The linesare then laid out across the front and back wall in the line grooves andconnected tightly to the eyes in the bridge.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pneumatic line into the enclosure. But it may bepreferable to have the sensor operate by using RF technology to transmitand receive the requisite information as necessary.

The lines may then be automatically tightened according to informationprovided by the pressure sensor. This would normally occur when apressure sufficiently above atmospheric is created by the pressurevarying means within the enclosure.

Example 3 (Strut Force Generating Means—Fixed Wall)

Prepare a frame having three to five millimeters thickness. Hermeticallyattach a back plate or wall to this frame, preferably made from amaterial having one tenth the acoustic impedance of the frame material.The attachment may be made by means of an attachment frame that fitsover the back plate and hermetically seals it against the frame. Theattachment frame may be made of either the frame material or the backplate material. And the frame and the attachment frame may be made ofmetal or any other material capable of the handling of forces upwards ofone hundred pounds.

The frame should have an opening for accepting the hermetic placement ofan external valve. This valve will have a conduit to the interior of theenclosure and on the external side enable connection to a pressurevarying means including the means for admitting and removing.

Attach struts in a geometrically uniform pattern to the back plate (Ageometrically uniform pattern may involve placing the struts in aconnected triangular configuration, in a connected square configuration,in a connected pentagonal configuration, etc.). The distance between thestruts and the number of struts must be calculated by taking in toaccount the maximum possible force on the back or front plate anddividing that by the bearing capacity of a strut and also taking intoaccount the bearing and flexure properties of the front or back plateand frame etc. In general one strut per square inch should be sufficientfor most materials which might comprise the struts.

Furthermore, the struts (which would in this embodiment be about threemillimeters long, and no longer than five millimeters) are preferablymade from a back and front material, the front material having one tenththe acoustic impedance of the back material. This creates a naturalsound reflectance so that sound transmitted through the front plate intothe front material of a strut will substantially be reflected by theback material of the strut, thereby minimizing sound transmissionthrough the strut and enclosure. If the frame is preferably constructedusing the same technological principles as are used for the struts, aminimizing of sound transmission through the frame will also occur.However, it is usually preferable to select the front attachment frameto have about one tenth the acoustic impedance of the frame so that theincreased reflectance occurs at the boundary between the attachmentframe and frame. This allows the frame to be made of one material.

The back and front plates may be manufactured with nodal plates into oronto which the struts can conveniently be fitted. And after the strutshave been attached to the back plate the front plate is fitted over thestruts and hermetically attached to the frame. The attachment may bemade by means of an attachment frame that fits over the front plate andhermetically seals it against the frame. The attachment frame may bemade of either the frame material or the front plate material. And theframe and the attachment frame may be made of metal or any othermaterial capable of the handling of forces upwards of one hundredpounds. The enclosure is finished after the attachment of the frontplate but may also have a holder for attaching the frame to a servomechanism driven by an electric motor. The servomechanism wouldgenerally be a pole or arm for holding the enclosure in the physicalspace, but it would also be capable of rotation and angular movementunder the action of the electric motor.

The enclosure need not be square but it should always follow theconformation of a hollow sheet. By changing the degree of evacuationwith the pressure varying means and the positioning of the enclosurewith the servomechanism, dynamic sound baffling can be implemented. Andthe struts and the frame or attachment frame may also comprise enclosuretransduction nodes for actively modifying and controlling the soundpassing through the struts and the frame.

Example 4 (Spring Force Generating Means—Fixed Walls)

Prepare a frame having three to five millimeters thickness or any otherthickness that may be preferable. Hermetically attach a back plate orwall to this frame, preferably made from a material having one tenth theacoustic impedance of the frame material. The attachment may be made bymeans of an attachment frame that fits over the back plate andhermetically seals it against the frame. The attachment frame may bemade of either the frame material or the back plate material. And theframe and the attachment frame may be made of metal or any othermaterial capable of the handling of forces upwards of one hundredpounds. The frame should have an opening for accepting the hermeticplacement of an external valve. This valve will have a conduit to theinterior of the enclosure and on the external side enable connection toa pressure varying means including the means for admitting and removing.

Attach springs in a geometrically uniform pattern to the back plate (Ageometrically uniform pattern may involve placing the springs in aconnected triangular configuration, in a connected square configuration,in a connected pentagonal configuration, etc.). The distance between thesprings and the number of springs required, could be calculated bytaking into account the maximum possible force on the back or frontplate and dividing that by the bearing capacity of a spring and alsotaking into account the bearing and flexure properties of the front orback plate etc. In general one spring per square inch should besufficient for most materials which might comprise the springs.

Furthermore, the springs (which would in this embodiment be about threemillimeters long, and no longer than five millimeters) are preferablymade from the same material as the frame. This takes advantage of anatural sound reflectance so that less sound should be transmittedthrough the front plate into a spring, thereby reducing soundtransmission through the spring.

The back and front plates may be manufactured with back and front nodalplates into or onto which the springs can conveniently be fitted. Andafter the springs have been attached to the back plate the front plateis fitted over the springs and hermetically attached to the frame. Theattachment may be made by means of an attachment frame that fits overthe front plate and hermetically seals it against the frame. Theattachment frame may be made of either the frame material or the frontplate material. And the frame and the attachment frame may be made ofmetal or any other material capable of the handling of forces upwards ofone hundred pounds.

The springs may also be used in combination with a solenoid to create aretracting node. The solenoid fits inside the spring and has a solenoidplate that is pressed by the spring to fit evenly against the frontnodal plate during operation. The other end of the solenoid is attachedto the rear nodal plate. When the solenoid is activated force is exertedpulling the solenoid plate back against the spring and compressing thespring, thereby creating a space between the spring and the front nodalplate. The entire assembly then functions as a retracting node.

Lastly the solenoid and the spring may be fastened to the back and frontnodal plates. In this embodiment, when the solenoid retracts it exerts acontracting force on the enclosure. This embodiment can therefore beused to counteract pressure greater than atmospheric that may be createdby the pressure varying means.

Example 5 (Line Force Generating Means—Flexible Walls)

Using a mold for preparing a rubber or plastic product, hermeticallyform an annular basin made of rubber or plastic or other moldablehermetic material, said annular basin molded in one piece with a rearwall.

After releasing the annular basin from the mold and testing the hermeticproperties of the basin, add attachment plates to the outside wall ofthe annular basin, as required. The attachment plates may be made ofmetal or any other material capable of being attached to the annularbasin, so that the handling of forces upwards of one hundred pounds isenabled.

Next attach a hermetic pipe valve to the surface of the annular basin sothat this valve is suitable for connection to a pressure varying meansand a means for admitting and removing. The hermetic pipe valve isconnected to the pressure varying means and in particular to the highpressure output which is used to increase the pressure in the annularbasin to above atmospheric or the reduction of the pressure in theenclosure to below atmospheric.

The front and back wall of the enclosure may have attachment platesalready attached to them. If not, after the front wall is attached,attach attachment plates to both the front and back wall, saidattachment plates further comprising lines attached to said attachmentplates. When the enclosure is evacuated the lines can be put undertension to counteract the external pressure when present. The annularbasin should also have attachment plates comprising lines which can betightened to counteract the external pressure, when present.

The attachment plates will have eyes or other attaching elements formaking attachments to the line force generating means. The line forcegenerating means will then be able to preferably position the enclosurein the physical space or it may exert forces to effect changes in theshape of the enclosure. These forces should be kept sufficiently smallso that the hermetic properties of the enclosure are not compromised.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by wiringmiming through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

The operation of this embodiment is governed by the line forcegenerating means. Starting with atmospheric pressure in the enclosure;when the enclosure is held under tension by the lines in the physicalspace under consideration the pressure varying means may be used toreduce the internal pressure within the enclosure. The basic operatingprinciple is that the external pressure acting on the enclosure is thencounteracted by the force exerted through the lines of the line forcegenerating means.

The tension on the lines may be increased or decreased by means ofpulleys attached to electric motors. Or the lines may be attached tosolenoids that increase the tension by retracting the lines. Manualoperation using a winch or its equivalent is optional.

Example 5 a (Example 5 Further Having an Electric Force Generating Meansfor Resisting Internal Pressure—Flexible Walls)

Construct and enclosure according to the procedure of example 5,ensuring that the annular basin is moulded suitably for the attachmentof a pressure varying means. Release the annular basin from the mold andtest the hermetic properties of the annular basin, when possible,

Before attaching the front wall to the annular basin, to the back wallattach small electromagnets that are organized into a rectangular gridwhich may be made of squares, each side of said squares comprised of oneof said small electromagnets. And after the same fashion, attach smallelectromagnets that are organized into a rectangular grid, which maymade of squares, to the front wall. The distance between theelectromagnets and the number of electromagnets must be calculated bytaking in to account the maximum possible pressure on the back and frontwall, including the pressure on the frame, and dividing that by thebearing capacity of the electromagnetic node, which is equivalent to oneintersection of the grid. The bearing and flexure properties of thefront or back wall etc. should also be taken into account. To get arough idea of the number of nodes required, the total expected pressurecan then be divided by the bearing capacity of the electromagnetic node.In general one grid square of electromagnets per square inch may be asufficient approximation for most conditions.

The back and front walls may be manufactured with attachments into oronto which the electromagnets can conveniently be fitted. Theattachments could be slots or holders designed to accept and hold theelectromagnets in position. And after the electromagnets have beenattached to the back wall and the front wall, the front wall ishermetically attached to the open side of the annular basin. Next addattachment plates to the outside wall of the annular basin, as required.The attachment plates may be made of metal or any other material capableof being attached to the annular basin so that the handling of forcesupwards of one hundred pounds is enabled.

The electromagnetic grids of the front wall may be simplified to useonly permanent magnets. In operation, an attractive polarity is neededwhen the pressure varying means is used to increase the pressure insidethe enclosure above atmospheric, while a repulsive polarity is requiredwhen the pressure within the enclosure is reduced below atmospheric.However, since the line force generating means of Example 5 is capableof handling compression of the enclosure, it is only necessary for theelectromagnets to operate in the attractive mode. In all instances thecontrolling means would, by using sensor info, ensure that the pressurescreated in the enclosure, or outside the enclosure, do not exceed therating of the force generating means (in this case the line forcegenerating means or the electric force generating means).

The electric nodes will have a repulsive polarity when theelectromagnets are selected to have opposite polarities for eachrectilinear grid on the front or back plates. Normally theelectromagnets are supplied with a current that creates a pattern of allsouth poles at one intersection of the rectilinear grid and all northpoles at another intersection of the rectilinear grid. Each north poleintersection of the grid will then be surrounded by south poleintersections and vice versa. To create attraction the back grid willthen have its north poles diametrically opposite the front grids southpoles and vice versa. To create repulsion the opposite is true, the backgrid will have its north poles diametrically opposite the front gridsnorth poles and vice versa. The amount of attraction or repulsion canthen be controlled by changing the electric current flow through theelectromagnets.

The operation of this embodiment is governed by the line forcegenerating means in combination with the electric force generatingmeans. Starting with atmospheric pressure in the enclosure; when theenclosure is held under tension by the lines in the physical space underconsideration the pressure varying means may be used to reduce theinternal pressure within the enclosure. The basic operating principle isthat the external pressure acting on the enclosure is then counteractedby the force exerted through the lines of the line force generatingmeans. Alternatively if the internal pressure is increased the electricforce generating means can be used to counteract this increase.

The enclosure is finished after the attachment of the front wall but mayalso have holder for attaching the frame to a servo mechanism driven byan electric motor. The servomechanism would generally be a pole or armfor holding the enclosure in the physical space, but it would also becapable of rotation and angular movement under the action of theelectric motor.

Example 6 (A Lever Force Generating Means—Flexible Walls, ExternalNodes)

Using a mold for preparing a rubber or plastic product, hermeticallyform an annular basin made of rubber or plastic or other moldablehermetic material, said annular basin molded in one piece with a rearwall and; said annular basin further having an external central groove.

The annular basin may be made of rubber or plastic or any other moldablehermetic material, and may also have an opening for accepting theplacement of an external valve located on the surface of the annularbasin. This is only necessary when the connection of a pressure varyingmeans to the basin is contemplated and embodiments that do not use apressure varying means would not have this opening. After releasing theannular basin from the mold and testing the hermetic properties of thetube, attach an external frame by fitting the external frame into theexternal central groove. The external frame and the nodal attachmentplates may be made of metal or any other material capable of beingattached to the annular basin so that the handling of forces upwards ofone hundred pounds is enabled. Next, apply and hermetically seal a frontwall to the open side of the annular tube. Alternatively, the annularbasin could be molded in one piece with a rear and a front wall.

The external frame will have two connected gears axially mounted on eachside of the external frame. Each gear should have two pivots attached totwo levers connected to either the front or the back grid. The leversride on opposing fulcrums projecting from the external frame. The distalend of each lever is attached to either the front or the back grid andthe interstices of the respective grids are attached to nodal plates onthe front and back plates of the enclosure, respectively. The gearsshould be close enough to mesh so that when a gear is turned itscounterpart gear turns also and vice versa.

The front and back grids will be attached to nodal attachment plates onthe front and back wall of the enclosure. This attachment may be bylines or external struts or any other convenient mechanism. When thegears are turned to extend the levers, the distance between the grids isincreased, thereby causing the enclosure walls to move apart andcreating a vacuum within the enclosure. And a third gear is attached bya synchronizing shaft to its opposite number so that the two connectedgears axially mounted on each side of the external frame may besynchronized. Therefore the gears on both sides of the frame shouldrotate at the same rate and for the same distance. The third gear willco-ordinate the rotating force that may be applied by an active elementsuch as an electric motor. The electric motor may be connected to thethird gear and the synchronizing shaft, or it could be connected to oneof the other gears.

If the embodiment requires it, next attach a hermetic pipe valve to theoutside layer of the annular basin so that these valves are suitable forconnection to a pressure varying means and a means for admitting andremoving. The hermetic pipe valve is connected to the pressure varyingmeans and to the high pressure output which is used to increase thepressure in the annular basin to above atmospheric, or to reduce thepressure in the enclosure to below atmospheric.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

Example 7 (Electric Force Generating Means—Fixed Walls, Expanding Nodes)

Prepare a frame having three to five millimeters thickness or any otherthickness as may be preferable. Hermetically attach a back plate or wallto this frame, preferably made from a material having one tenth theacoustic impedance of the frame material. The attachment may be made bymeans of an attachment frame that fits over the back plate andhermetically seals it against the frame. The attachment frame may bemade of either the frame material or the back plate material. And theframe and the attachment frame may be made of metal or any othermaterial capable of the handling of forces upwards of one hundredpounds. The frame will have an opening for accepting the hermeticplacement of an external valve. This valve will have a conduit to theinterior of the enclosure and on the external side enable connection toa pressure varying means including the means for admitting and removing.

To the back plate attach small electromagnets organized into arectilinear grid, which may made of squares, each side of said squarescomprised of one of said small electromagnet. And after the samefashion, attach small electromagnets organized into a rectilinear gridmade of squares, to the front plate. The distance between theelectromagnets and the number of electromagnets must be calculated bytaking in to account the maximum possible expected force on the back orfront plate and dividing that by the bearing capacity of anelectromagnetic node, and also taking into account the bearing andflexure properties of the front or back plate etc. In general onerectangular element of the grid is made up of four electromagnetscomprising the four sides of the rectangular element, and may generallybe called and electric node. One electric node per square inch should bea sufficient approximation for most conditions.

The back and front plates may be manufactured with nodal plates into oronto which the electromagnets can conveniently be fitted. And after theelectromagnets have been attached to the back plate and the front plate,the front plate is hermetically attached to the frame. The attachmentmay be made by means of an attachment frame that fits over the backplate and hermetically seals it against the frame. The attachment framemay be made of either the frame material or the front plate material.And the frame and the attachment frame may be made of metal or any othermaterial capable of the handling of forces upwards of one hundredpounds. The electromagnetic grids of the front plate may be selected tohave an attractive polarity or a repulsive polarity. A repulsivepolarity is selected when the enclosure is under evacuation, while anattractive polarity is selected when the pressure varying means is usedto increase the pressure inside the enclosure above atmospheric.

The electric nodes will have a repulsive polarity when theelectromagnets are selected to have opposite polarities for eachrectilinear grid on the front or back plates. Normally theelectromagnets are supplied with a current that creates a pattern of allsouth poles at one intersection of the rectilinear grid and all northpoles at another intersection of the rectilinear grid. Each north poleintersection of the grid will then be surrounded by south poleintersections and vice versa. To create attraction the back grid willthen have its north poles diametrically opposite the front grids southpoles and vice versa. To create repulsion the opposite is true, the backgrid will have its north poles diametrically opposite the front gridsnorth poles and vice versa. The amount of attraction or repulsion canthen be controlled by changing the electric current flow through theelectromagnets.

The enclosure is finished after the attachment of the front plate butmay also have holder for attaching the frame to a servo mechanism drivenby an electric motor. The servomechanism would generally be a pole orarm for holding the enclosure in the physical space, but it would alsobe capable of rotation and angular movement under the action of theelectric motor.

The enclosure need not be square but it should always follow theconformation of a hollow sheet. By changing the degree of evacuationwith the pressure varying means and the positioning of the enclosurewith the servomechanism, dynamic sound baffling can be implemented.

Example 8 (Line Force Generating Means for Constructing an AcousticLens; Internal and External Nodes, Flexible Walls)

Using a mold for preparing a rubber or plastic product, hermeticallyform a tube having the shape of an elliptic paraboloid when placed underinternal pressure.

The tube made of rubber or plastic or any other moldable hermeticmaterial, may also have openings for accepting the placement of anexternal valve located in the outside layer of the tube. And the pipemay also be used to carry an electric conductor into the tube.

After releasing the pneumatic tube from the mold and testing thehermetic properties of the tube, add attachment plates to the outsideand inside of the tube wall, as required. The attachment plates may bemade of metal or any other material capable of being attached to thetube so that the handling of forces upwards of one hundred pounds isenabled.

Next attach a hermetic pipe valve to the outside layer of the tube sothat this valve is suitable for connection to a pressure varying meansand a means for admitting and removing. The hermetic pipe valve isconnected to the pressure varying means by a pipe and in particular canmake a connection to the high pressure output of the pressure varyingmeans which could be used to increase the pressure in the tube to aboveatmospheric, and create the convex effect of the elliptic paraboloidshape for the tube.

Next attach attachment plates to both sides of the elliptic paraboloidtube, the attachment plates further comprising lines attached to theattachment plates. The attachment plates will have eyes or otherattaching means to which the lines of the line force generating meansmay be attached. The line force generating means will then be able toposition the enclosure in the physical space or it may exert forces toeffect changes in the shape of the enclosure by adjusting and tensioningthe lines. These forces should be kept sufficiently small so that thehermetic properties of the enclosure are not compromised.

The internal lines having a connection to the attachment plates insidethe tube are further connect to a central line node, having electricmotors and/or solenoids, or other means, for tightening the interiorlines as may be required. When the tension on the lines from the centralnode is increased, corresponding lines attached to the exteriorattachment plates may have their tension reduced, to allow that sectionof to tube to be pulled in. This adjustment can be continued until theelliptic paraboloid shape is converted to the shape of a convex lens.

When the enclosure is evacuated the exterior lines can be put undertension to counteract the external pressure when present. This may beaccomplished by running the lines over pulleys slaved to electric motorsthat are used to exert tension on the lines. And solenoids may beattached to the lines so that when they are actuated the lines aretightened so that the convex or concave shape of the acoustic lens ismade evident, as may be preferable.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

The operation of this embodiment is governed by the line forcegenerating means. Starting with atmospheric pressure in the enclosure;when the enclosure is held under tension by the lines in the physicalspace under consideration the pressure varying means may be used toreduce the internal pressure within the enclosure. The basic operatingprinciple is that the external pressure acting on the enclosure is thencompensated for by the force exerted through external lines by the lineforce generating means. Alternatively, the pressure varying means may beused to increase the internal pressure within the enclosure. The basicoperating principle is that the internal pressure then acting on theenclosure is then compensated for by the force exerted through thecentral node and the internal lines by the line force generating means.

The tension on the lines may be increased or decreased by means ofpulleys attached to electric motors. Or the lines may be attached tosolenoids that increase the tension by retracting, possibly incombination with levers or a lever force generating means.

Example 9 (Line Force Generating Means Combined with a Pneumatic ForceGenerating Means and a Spring Force Generating Means to Create aTetrahedron (Polyhedron); Internal and External Nodes, Fixed Walls)

Prepare a frame having three to five millimeters thickness, or any otherthickness as may be preferable. Hermetically attach a back plate or wallto this frame, preferably made from a material having one tenth theacoustic impedance of the frame material. The attachment may be made bymeans of an attachment frame that fits over the back plate andhermetically seals it against the frame. The attachment frame may bemade of either the frame material or the back plate material. And theframe and the attachment frame may be made of metal or any othermaterial capable of the handling of forces upwards of one hundredpounds. The frame will have an opening for accepting the hermeticplacement of an external valve. This valve will have a conduit to theinterior of the enclosure and on the external side enable connection toa pressure varying means including the means for admitting and removing.

The frame will furthermore have a triangular shape suitable forcomprising one side of a tetrahedron and central grid notches foraccommodating an internal grid by fitting the internal grid into theinternal grid notches. The internal grid will have grid holders forattaching to the central grid notches and nodal holders for holding onto the sets of parallel cross-linking springs. The first set of parallelcross-linking springs is attached to the nodal holders of the internalgrid and to the rear of the internal grid. Then the internal grid isfurther attached by nodal holders to a second set of mutually parallelcross-linking springs attached to the front of the internal grid. Thefirst and second set of parallel cross-linking springs runperpendicularly to each other.

And after the cross-linking springs have been attached to the internalgrid, the front plate is hermetically attached to the frame. Theattachment may be made by means of an attachment frame that fits overthe back plate and hermetically seals it against the frame. Theattachment frame may be made of either the frame material or the frontplate material.

Next add attachment plates to the outside wall of the frame, ifrequired. In particular the vertices on the triangles should haveattachment plates so that a line force generating means can be appliedto them. The internal grid and the attachment plates may be made ofmetal or any other material capable of being attached to the frame sothat the handling of forces upwards of one hundred pounds is enabled

Next, create three more triangular enclosures as shown above, so thatthey can be joined together to comprise the tetrahedral polyhedron ortetrahedron, Create a pneumatic tube that can be joined to the verticesof the tetrahedron. The pneumatic tube should be divided into sectionsof a length corresponding to the length of the sides of the tetrahedron.The pneumatic tube could have a connection to the pressure varying meansor it could be filled independently through a regular high pressurevalve. The pneumatic tube is sealed to the edges of the tetrahedron andprovides stability and resilience to the geometry of the tetrahedron.

The attachment plates will have eyes or other attaching means forconnecting to the lines of the line force generating means. The lineforce generating means will then be able to position the enclosure inthe physical space under consideration. The forces should be keptsufficiently small so that the hermetic properties of the enclosure arenot compromised. In any event, at least four lines should be attached tothe tetrahedron, each vertex having at least one line attached to it.

A pressure sensor may also be added to the interior of the enclosureprior to adding the front wall. The sensor could be operated by a wirerunning through the pipe insert or the pipe and into the enclosure. Butit may be preferable to have the sensor operate by using RF technologyto transmit and receive the requisite information as necessary.

The operation of this embodiment is governed by the pressure varyingmeans in combination with the line force generating means and the springforce generating means. Starting with atmospheric pressure in theenclosure; when the enclosures are held under tension in the tetrahedralconfiguration by the lines in the physical space under consideration thepressure varying means may be used to reduce the internal pressurewithin the enclosure. The basic operating principle is that the externalpressure acting on the enclosure is then compensated for by the forceexerted through the springs be the spring force generating means.

The tension on the lines may be increased or decreased by means ofpulleys attached to electric motors. Or the lines may be attached tosolenoids that increase the tension by retracting.

Example 10 (Electric Force Generating Means Having a Positive StaticVoltage Output Pole—Flexible Walls)

An electric force generating means may be used to maintain the enclosurewalls against internal or external pressures. Construct the enclosurefrom a light hermetic material that preferably is capable of forming aflexible wall. Apply a conductive coating to the inside of theenclosures. This may be done by using a conductive spray or paint, or itcould be done by laminating exposed conductive foil (aluminum foil) tothe inside of the enclosure wall. And this may be put to use in twoembodiments.

The first embodiment would have the conductive coating appliedcontinuously over the entire interior surface of the enclosure. Thesecond embodiment would have the conductive coating applied separatelyto the front and back wall of the enclosure, so that there is noconduction between the conductive coatings of the front and back wall.The conductive coatings will also have contact plates connected towires. The wires in turn are connected to the negative charge reservoiror the switch by a pole wire.

After the enclosure walls (Both walls should have the same size anddimensions; they should be geometrically congruent.) have been preparedthey are placed on a flat work bed and aligned to overlap exactly. Thena press for eliminating air voids between the enclosure walls shouldapply pressure to all of the enclosure walls excepting the border, rim,or frame area of the wall. After the pressure has eliminated the airvoids from between the enclosure walls, the frame area of the enclosurewalls is hermetically sealed and laminated together, leaving only thepole wire extruding from the enclosure. After the pole wire is encasedin a suitable sealing plug. the loci in the enclosure where the polewire exits the enclosure is also carefully hermetically sealed with thesealing plug being inserted and sealed into the enclosure. The press isthen removed and the power supply is added to the enclosure and the polewire is connected to the static voltage output pole of the power supply.

The power supply may be contained in a casing attached to the enclosureand have a manual control for controlling the rate at which charge isbeing transferred to the charge plates. (When complex embodiments havingmany enclosures are created the power supply may be a stand-alone unitand the power should then be carried to the enclosures by a plurality ofpole wires.) And the enclosure may also have a number of RF transmitterfeedback circuits for signaling the separation between the enclosurewalls. The power supply will then have a control for setting thepreferred distance of separation between the two walls of the enclosure.And the RF feedback circuit could signal the power supply to change therate at which charge is being transferred, as may be preferable.Therefore, when using a Van de Graaff generator the control would simplysignal the drive motor to speed up or slow down, as required. When usinga Tesla coil, a variable primary may be used to vary the output power asdictated by the control. And inserting a variable resistance into thecharging circuit may preferably be used to regulate the amount of chargeadded by the Tesla coil. Also a lower voltage coil may be used instead.

A source of electric charge is required; this may be obtained by using avan de Graaff generator, a Marx bank, or a Tesla coil etc., which forconvenience throughout this text may be referred to as a high voltagepower supply. The high voltage power supply is attached by wiring to anegative charge reservoir and a positive charge reservoir, and can beused to supply either reservoir with the appropriate charge as indicatedby the reservoir name. The charge reservoir may also have insulationapplied to it, to prevent charge leakage from the reservoir to theatmosphere. And the output of the power supply should have a staticvoltage output pole for making connection with the pole wire.

The first embodiment is usually connected to the negative chargereservoir, although it could also be connected to the positive chargereservoir. In any event the charge on the conductive coating of thisembodiment will always be uniformly negative, or positive.

The second embodiment may have the same charge on both conductivecoatings, but also has a switch that provides the option of switching toan arrangement where the conductive coatings are charged to oppositepolarities. The switch is connected to the bipolar conductive coating bya wire and has a first contact point and a second contact pointconnected by wires to the negative charge reservoir and the positivecharge reservoir, respectively. The other conductive coating ispermanently connected to either the negative or the positive chargereservoir.

This implies that the switch can render the electrostatic force actingin the second embodiment either attractive or repulsive depending onwhether the polarities are opposite or negative or positive.

The preferred distance between the walls of this embodiment is fromabout 1 millimeter to about 5 millimeters, or more preferably from about2 mm. to about 4 mm., or most preferably at about 3 mm. At this distancea minor amount of charge should be effective to achieve separationbetween the walls by creating repulsion between the walls. Theregulation of the amount of charge that is added can be carried out in anumber of ways. If a van de Graaff generator is used, then regulationcan be achieved by simply varying the speed of the motor that drives thegenerator. Alternatively when a high voltage coil arrangement such as aTesla coil is used, inserting a variable resistance into the chargingcircuit can be used to regulate the amount of charge added. And avariable primary may also be used to vary the output power as dictatedby the control.

A loop shaped to conform to the perimeter of the enclosure wall may befashioned from resilient wire or plastic, or any other suitablematerial. The loop may be added or attached to the perimeter of theenclosure to keep the enclosure fully stretched and taut and to keepfolds from appearing on the enclosure surface. To complete the frame ofthe enclosure, the loop would then preferably be connected to the powersupply casing.

This embodiment FIG. 53, should therefore function well when dealingwith enclosures of light construction.

Example 11 (Electric Force Generating Means Having a Positive StaticVoltage Output Pole and a Plurality of Charge Plates—Flexible Walls)

An electric force generating means may be used to maintain the enclosurewalls against internal or external pressures. Construct the enclosurefrom a light hermetic material that preferably is capable of forming aflexible wall. Apply a grid of conductive plates to what will become theinside surface of the flexible enclosure wall. This may be done by usinga conductive spray or paint in combination with a masking stencil toensure that areas of the inside surface will remain non-conductive, orit could be done by laminating conductive foil plates (aluminum foilcould be used) to the inside surface of the flexible enclosure wall.Next, a wiring grid is laid out on the inside surface of the flexibleenclosure wall, so that each of the conductive plates is connected to aseparate wire or conductive lead of the wiring grid. The conductiveplates should have just enough separation to allow the wiring grid to belaid out without incurring the danger of a short circuit. A thin plasticinsulating sheet of minimum thickness may also be applied over theconductive plates and the wiring grid after they have been laid on. Andit may be preferable to use diodes in the connection of each of theconductive plates to the wiring grid; this should enable the conductiveleads to be connected to feeder wires which in turn could be connectedto a pole wire that connects to the static voltage output pole of thepower supply. The diodes are placed so as to only allow charge transferfrom the output pole to the charge plates. Current flow from the chargeplates to the output or to other charge plates is blocked by the diodes.This should greatly simplify the construction of the wiring grid.

For a single enclosure, the power supply would generally be located in acasing that is attached to the enclosure. (When complex embodimentshaving many enclosures are created the power supply may be a stand-aloneunit and the power should then be carried to the enclosures by aplurality of pole wires.) If the enclosure is meant to be hung from aceiling or other support, the power supply casing may reside at the topof the enclosure. If the enclosure were made to rest on the floor, thepower supply casing would generally reside at the bottom of theenclosure. And the power supply is simply a source of electric charge asmay be provided by a Van de Graaff generator, a Tesla coil, althoughlower voltage coils may suffice, or any other electrostatic chargegenerating device capable of providing the requisite amount of charge tothe charge plates.

After the enclosure walls (Both walls should have the same size anddimensions; they should be geometrically congruent.) have been preparedthey are placed on a flat work bed and aligned to overlap exactly. Thena press for eliminating air voids between the enclosure walls shouldapply pressure to all of the enclosure walls excepting the border, rim,or frame area of the wall. After the pressure has eliminated the airvoids from between the enclosure walls, the frame area of the enclosurewalls is hermetically sealed and laminated together, leaving only thepole wire extruding from the enclosure. After the pole wire is encasedin a suitable sealing plug, the loci in the enclosure where the polewire exits the enclosure is also carefully hermetically sealed with thesealing plug being inserted and sealed into the enclosure. The press isthen removed and the power supply is added to the enclosure and the polewire is connected to the static voltage output pole of the power supply.

The power supply may have a manual control for controlling the rate atwhich charge is being transferred to the charge plates. And theenclosure may also have a number of RF transmitter feedback circuits forsignaling the separation between the enclosure walls. The power supplywill then have a control for setting the preferred distance ofseparation between the two walls of the enclosure. And the RF feedbackcircuit will signal the power supply to change the rate at which chargeis being transferred, as may be preferable. In either case, when using aVan de Graaff generator the control would simply signal the drive motorto speed up or slow down, as required. When using a Tesla coil, avariable primary may be used to vary the output power as dictated by thecontrol. Also, inserting a variable resistance into the charging circuitcan be used to regulate the amount of charge added by the Tesla coil.Also a lower voltage coil may be used instead. The dome of the van deGraaff generator or the torus of the Tesla coil may also have insulationapplied to it, to prevent charge leakage into the atmosphere. And theoutput of the power supply should have a static voltage output pole formaking connection with the pole wire.

The preferred distance between the walls of this embodiment is fromabout 1 millimeter to about 5 millimeters, or more preferably from about2 mm. to about 4 mm., or most preferably at about 3 mm. At this distancea minor amount of charge should be effective to achieve separationbetween the walls by creating repulsion between the charge plates. Andadding more charge will have the effect of overcoming the externalpressure that is created by the atmosphere.

And a loop shaped to conform to the perimeter of the enclosure wall maybe fashioned from resilient wire or plastic, or any other suitablematerial. The loop may be added or attached to the perimeter of theenclosure to keep the enclosure fully stretched and taut and to keepfolds from appearing on the enclosure surface. To complete the frame ofthe enclosure, the loop would then preferably be connected to the powersupply casing.

The electric force generating means controls this embodiment. A meansfor varying is not required since the vacuum is created when the emptyor non-existent space between the enclosure walls is expanded.

Example 11a (Example 11 Having a Positive and a Negative Static VoltageOutput Pole—Flexible Walls)

This embodiment would have the charge plates of the first wall of theenclosure connected to the positive static voltage output pole and thecharge plates of the second wall of the enclosure connected to a switch.The switch in turn is capable of making electrical connection witheither the positive or the negative static voltage output pole or thepower supply.

The embodiment of Example 11 is usually connected to the positive chargereservoir, although it could also be connected to the negative chargereservoir. In any event the charge on the conductive coating of thisembodiment will always be uniformly negative, or positive.

Example 11a may have the same charge on the conductive plates of bothenclosure walls, but it also has a switch that provides the option ofswitching to an arrangement where the conductive plates on the firstenclosure wall are charged to the opposite polarity or the conductiveplates on the second enclosure wall. The switch is connected to theconductive plates on the second enclosure wall by the wiring grid, andhas a first contact point and a second contact point connected by wiresto the negative charge reservoir and the positive charge reservoir,respectively. The conductive plates of the first enclosure wall arepermanently connected to either the negative or the positive staticvoltage output pole. And the wiring grid of this embodiment is splitinto two parts, the first part of the wiring grid making electricconnection to the first enclosure wall and the second part of the wiringgrid making electric connection to the second enclosure wall.

This implies that the switch can render the electrostatic force actingin this embodiment either attractive or repulsive depending on whetherthe polarities are opposite or negative or positive. And the positiveand negative static voltage output poles of the power supply can becharged by using two Van de Graaff generators, one with a negativestatic voltage dome, and the other with a positive static voltage dome.Alternatively two Tesla coils could be used instead, although lowervoltage coils may suffice.

Example 11b (Example 10, 11, or 11a, Further Having a Pressure VaryingMeans—Flexible Walls)

Example 10, 11, or 11a, could further have a pressure varying meansadded to them.

In this embodiment a hermetic pipe valve may be attached to theenclosure so that this valve is suitable for connection to a pressurevarying means and a means for admitting and removing. The hermetic pipevalve is connected to the pressure varying means by a hermetic pipe ortube and in particular can make a connection to the high-pressure outputof the pressure varying means that could be used to increase thepressure in the enclosure to above atmospheric. Or the means foradmitting and removing could lower the pressure to below atmospheric.

Using a pressure varying means allows the enclosure to have variablesound and temperature transmission, whereas the embodiments of Example10, 11, or 11a, were only capable of switching between total soundbaffling and total sound transmission. This embodiment may therefore beused when more flexibility in the handling of sound is desired.

If a pressure varying means is used in combination with Example 11, orthe first embodiment of Example 10, only the means for admitting andremoving should be allowed to operate, since Example 11, or the firstembodiment of Example 10, are only capable of creating repulsion. If thefull scope of the pressure varying means is to be applied Example 11amust be used because it can switch from the repulsive state to theattractive state. The charge plates will have to enter the attractivestate to overcome the internal pressure that could be created by themeans for varying.

Example 11c (Example 11 or 11a or 11b Further Having a NodalMeans—Flexible Walls)

It may be preferable to add a nodal means for controlling the chargeplates. A nodal means can be constructed by using SCRs instead ofdiodes. The SCRs will be triggered by an output from a PROM nodal chipor a standard chip that is capable of serving as a nodal chip andhandling the specific electronic problem to suit.

The nodal chip essentially controls the activation of the SCRs to theconductive state and will have one output for each of the SCRs in theenclosure. Therefore the nodal chip can switch any permutation of SCRsinto the conductive state, thereby allowing the corresponding chargeplates to be charged.

On the input side the nodal chip will have the ability to receive asignal from the controlling means and to convert that signal into adigital representation presented on the nodal chip output leads, ascomprising either activating voltages for the SCRs or comprising neutralvoltages that are insufficient to activate the SCRs. Therefore for eightcharge plates in the enclosure, eight output leads would be required.For sixteen charge plates, sixteen output leads would be required. Andif the number of charge plates rises further, a single chip may notsuffice and an electronic nodal circuit may have to be constructed sothat the appropriate number of output leads is made available to controlthe SCR's.

A vacuum may also be used to improve the sound baffling characteristicsof ear protectors and head phone sets. As is well known the earprotectors are used to protect the ears from excessive ambient noise.And a prevalent problem with head phone sets is the interference ofambient noise with the audibility and perceived rendition of therendered sound. This may be alleviated by introducing an vacuum forbaffling the ambient noise. However there are some other sound bafflingimprovements that may be made to ear protectors and head phone sets aswell.

Accordingly, a more specific aspect of the invention is shown in FIGS.14 and 15 which depicts the invention in combination with a set of earprotectors having two sound baffling cups (354, 356) for fully enclosingthe ears between said sound baffling cups and the head and neck duringoperation, and a fitting means (358) for placing said sound bafflingcups against the ears, the improvement comprising;

A cushioned lip contour (360, 362) for complimenting the shape of thehead and neck during operation, said cushioned lip contour applied tothe lips (364, 366) of said sound baffling cups such that said cushionedlip contour curves the lips of said sound baffling cups laterally (368)away from the head where it touches the jaw bone and the side arch ofthe skull, and said cushioned lip contour curves the lips of said soundbaffling cups medially (370) towards the head and neck where it touchesthe human body surface beneath the jaw bone and behind the lowerexternal ear,

so that the comfort, fit, and sound baffling qualities of said soundbaffling cups are substantially improved by said cushioned lip contour,thereby reducing the ambient noise reaching the ears during operation.

Some previously available devices did not have contours. As shown inFIG. 15, since the head and neck have numerous contours, a contoureddevice provides a better fit and comfort. Also the exclusion andbaffling of sound is to some extent dependent on the ability of thesound baffling cups to seal against the head and neck, because thisprevents the sound from entering through gaps where the lips of thesound baffling cups are joined against the head and neck. A cushionedlip contour aids in achieving a proper seal, especially under conditionsof stress, where the head and neck are bent or when the sound bafflingcups are jarred by external contact.

If we consider the lips of previously available sound baffling cups tolie in a sagittal plane parallel to the side of the head duringoperation, then the cushioned lip contour diverges from this plane bycurving laterally (368) away from the head and neck directly above thejaw bone (372). Beneath the jawbone and the lower external ear (374) thecontour diverges from this plane by curving medially (370) towards thehead and neck. This compensates for the hollow of the human body surfacefound just beneath where the head and neck and jaw bone join. Then,behind the external ear, the contour moves back towards and into thisplane, lying substantially in this plane above the external ear.

It may be preferable to wear sound baffling cups having a lip contour incombination with a headband. The sound baffling cups may come with orwithout internal speakers. One such combination uses a reversibleheadband clip attached to the exterior surface of the sound bafflingcups so that the headband clip may be extended upward to hook over theheadband, or the headband clip may be reversed to extend downward toallow the headband to be fitted between the headband clip and theoutside of the sound baffling cups.

When the headband clip is extended upward the sound baffling cups mayalso have a neck straps attached to a strap attachment. The neck strapsare used to fit the sound baffling cups against the ears. When theheadband clip is extended downward the sound baffling cups can be usedwith a regular headband fitted through the headband clip, although theheadband has to be worn at a steep angle to allow the sound bafflingcups to fit properly against the ears.

And the sound baffling cups may have two fixed headband clips attachedto their exterior. The first fixed headband clip is attached at thecenter of the dorsal face of the sound baffling cups. The second fixedheadband clip is slightly lower than the first and offset to theanterior of the sound baffling cups. The sound baffling cups can be usedwith a regular headband fitted through the fixed headband clips,although the headband has to be worn at a steep angle to allow the soundbaffling cups to fit properly against the ears.

The sound baffling cups may also come with a surrogate headbandattached. The surrogate headband will come in two parts, the first partattached to the anterior of the sound baffling cups and the second partattached to the posterior of the sound baffling cups. When a surrogateheadband is attached, the sound baffling cups should not have a lipcontour; instead they should have an annular opening resident in oneplane.

This embodiment may be worn in the regular headband style or it may beworn with the band looping around the top of the head and underneath thechin. Because the cups must shift position when worn in one style or theother, the lip contour would not be appropriate for this embodiment.However, a lip contour may be used with this embodiment when theintended use is restricted to one of the two styles.

And complementary contours may be custom made by using a mold made fromcastings of the external ear. It may therefore be preferable that thecomplementary contour of said fitting means is created by a mold madefrom castings of a specific external ear, so that the complementarycontour of said fitting means is customized to fit said specificexternal ear. Such a mold may be made from standard casting techniquesand can then be used to create complimentary contours for customizedhead phone sets and ear protectors.

However, to minimize the sound that may travel through gaps between thecontour and the external ear during operation, a skin adhering materialmay be used. It may therefore be preferable that said cushioningmaterial or complementary contour has a binding preference for skin,said binding preference substantially sealing said cushioning materialor complementary contour against the external ear, so that the fit andsound baffling characteristics of said device are substantiallyimproved.

As further shown FIGS. 21, 22, 23, and 24, according to anotherparticular the invention is comprised of a jointed flexible curved cliphaving two parts, the first part (460) shaped to fit the curvature ofthe anterior half of the lip (462) of said sound baffling cups, thesecond part (464) shaped to fit the curvature of the posterior half ofthe lip of said sound baffling cups, and;

the first part of said jointed clip attached by a first hinge (466) to afirst pivot (468) mounted in a seat (470) projecting from the inferiorpart of said sound baffling cups, the second part of said jointed clipattached by a second hinge (472) to a second pivot (474) mounted in thedistal end of said first part, and;

the first and second parts of said jointed clip further having a lipgroove (476, 477) for accommodating the lip of said sound baffling cups,the distal end of the second part further having a tongue (478) forlatching into a tongue groove (480) located on the lateral surface (481)of said seat, such that said jointed clip further provides a firmbacking for the external ear when locked in place by said lip groove andby said tongue groove, and;

the lateral surface (482) of said jointed clip having supportingmaterial (483) for sealing said jointed clip against the ear lobe, sothat when said jointed clip is pivoted to fit the lip of said soundbaffling cups into said lip groove and latch said tongue in said tonguegroove during operation, the supporting material of said lateral surfaceof said jointed clip presses laterally to seal the ear lobe against asurface selected from the group consisting of the complementary contouror the cushioning material, as the case may be, and;

the medial surface (484) of said jointed clip having a wedge shapedlayer of bracing material (486) applied to it, the thicker part of saidwedge shaped layer attached to the posterior circumference (488) of saidsecond part, the thinner part of said wedge shaped layer comprising afrontal pad (490) for sealing and fitting the anterior part of saiddevice against the head and jawbone, and;

said bracing material further having a lip contour (492) forcomplementing the shape of the head and neck during operation, such thatsaid lip contour curves the bracing material of said jointed cliplaterally away from the head where it touches the jaw bone and the sidearch of the skull, and said lip contour curves the bracing material ofsaid jointed clip medially towards the head and neck where it touchesthe human body surface beneath the jaw bone and the external ear,

so that when said sound baffling cups (494) are locked in place by saidjointed clip the posterior of said sound baffling cups is movedlaterally by said wedge shaped layer of bracing material, therebypressing and sealing the frontal pad against the head and jaw bone.

This embodiment is one of several that may be used to hold soundbaffling cups against the ears. The clip is comprised essentially of twosemicircular arcs that have a width greater than the width of the lipsof the sound baffling cups. The width must also be sufficient forwedging the ear lobe upward against the cushioning material or thecomplementary contour as the case may be. The first part of the clip isattached by a first hinge to a first pivot located in a seat projectingfrom the inferior part of the sound baffling cups. The second part ofthe clip is attached by a second hinge to a second pivot attached to thedistal end of the first part of the clip. Also the clips are designed toprovide a firm backing for the ear lobe and the lips of the soundbaffling cups when locked in place. They are aided in this by the lipcontour and the wedge shape of the bracing material. The resulting shapebraces the assembly against the head and neck and also preventsperipheral sound from penetrating through the ear lobe.

To fit the sound baffling cups against the ears, the clips are rotatedaway from the sound baffling cups to allow the sound baffling cups to beplaced against the ears. The first part of the clip is then rotated tofit around the anterior part of the external ear until the lip of thesound baffling cups catches in the lip groove of the clip. Thereafter,the second part of the clip is rotated to fit behind the ear lobe untilthe lip of the sound baffling cups catches in the lip groove of thesecond part of the clip and the tongue latches in the tongue groove.When this operation is completed the clip will be pushing the ear lobelaterally into the complementary contour or the cushioning material asthe case may be, thereby effectively sealing the external ear againstthe sound baffling cups.

The sealing of the ears is further aided by the lip contour applied tothe medial surface of the wedge shaped layer of bracing material. Thesecond part of the jointed clip occupies a space dimensioned somewhatlike a large orange slice, with the thick part of the slice positionedalong the posterior circumference of the sound baffling cups. Hence,when locked in place with the lip contoured bracing material wedgedagainst the head and neck, the jointed clip forces the rear of the soundbaffling cups and the ear lobe away from the head and neck. This in turnforces the front of the sound baffling cups inward, thereby increasingthe sealing effect.

Alternatively as shown in FIG. (25, 26, 27, 28, 29), the latching meansmay be comprised of a sliding clip (500) which is attached to theposterior half of the sound baffling cups (501). Essentially the slidingclip performs the same function as, and has a second arc shaped flange(502) dimensioned somewhat like the second part of the jointed clip. Thefirst part of the jointed clip now appears as a first arc shaped flange(504) fused with the anterior half of the sound baffling cups andoccupying substantially the same dimension and position as the firstpart of the jointed clip occupies during operation.

However, the sliding clip also has a lune shaped shell (506) having acurvature corresponding to the shape of the sound baffling cups to whichit is attached. This lune shaped shell fits laterally over the posteriorpart of the sound baffling cups and is attached to the sound bafflingcups by a holding means which may be comprised of two strips or bands ofelastic material (512, 514) which are held in place by washers or plates(516, 517, 518, 519) that are cemented or fixed into the walls of thesliding clip or sound baffling cups. As shown in the drawings, theholding means allows the elastic material to be attached to both thelateral surface of the sound baffling cups and to the medial surface(520) of the sliding clip.

In operation the sliding clip is pulled back to allow the sound bafflingcups to be placed against the external ear so that the first arc shapedflange is wedged in behind the anterior part of the external ear. Then,in the presence of the elastic tension, the sliding clip is guidedforward so that the lune shaped shell is positioned proximally to thelateral surface (508) of the sound baffling cups. Simultaneously thesecond arc shaped flange, which is a part of the sliding clip, slidesforward to fit in behind the posterior part of the external ear andsubstantially seal the second arc shaped flange against the posteriorexternal ear and against the first arc shaped flange.

To further improve its fit the sliding clip also has a lip groove foraccommodating the posterior lip of the sound baffling cups. And when thesliding clip is pushed forward to mate with the sound baffling cups, inthe region where the first and second arc shaped flanges overlap, thesecond arc shaped flange fits laterally over the first arc shapedflange. As well, the first and second arc shaped flange have asupporting material (524, 526) for sealing the sliding clip against theear lobe attached to their lateral surface. And the medial surfaces(528, 530) of the first and second arc shaped flange may also have awedge shaped layer of bracing material (532) applied to them, so thatthe thicker part of the wedge shaped layer is attached to the posteriorcircumference (534) of the sliding clip and the thinner part of thewedge shaped layer comprises a frontal pad (536) attached to the firstarc shaped flange, for sealing and fitting the anterior part of thedevice against the head and jaw bone. As said before, the wedge shapedlayer of bracing material may also have a lip contour (538) forcomplementing the shape of the head and neck during operation. Hence,the posterior part of the device should be moved laterally by the wedgeshape of the bracing material during operation, so that the frontal padis braced against the head and jaw bone.

It has been shown by the preceding discussion that the external earprovides a great platform for attaching light devices to the head. Andthis is best done by using a clip that is capable of encircling theexternal ear in operation. This may be done by using a jointed clip, aflat sliding clip, a pneumatic clip, and a hydraulic clip.

It may therefore be preferable that according to one of its aspects theinvention further comprises; A latching means for proximally attachingelements to the ear, said latching means comprised of a plurality ofclips selected from the group consisting of a jointed clip, a flatsliding clip, a pneumatic clip, and a hydraulic clip.

The clips will have eyes or contact facets for allowing useful devicesto be attached to the clips so that they reside in functional proximityto the external ear. In particular the clips will be able to allow theattachment of sound baffling cups to the clips. The sound baffling cupsmay contain speakers for sound emission. And the clips should also allowthe attachment of external speakers; in fact it should be possible toattach more than one external speaker.

The clips may be constructed in a number of ways. The first is as shownin the embodiment of a jointed clip. The second is by using a flatsliding clip; the flat sliding clip is like the sliding clip except thatthe cup and shell have been omitted. If it is desired that soundbaffling cups are to operate in conjunction with the flat sliding clipthen the sound baffling cups would be attached to the flat sliding clipusing the eyes or contact facets. The flat sliding clip may use aholding means comprised of elastic bands as before, but the location ofthe holding means has shifted so that it is now located in the arcshaped flanges of the flat sliding clip.

Since the lune shaped shell is not an element of the flat sliding clip,the previous disposition of the holding means between the lune shapedshell and the sound baffling cups is no longer possible. And the joinbetween the arc shaped flanges has also changed. The second arc shapedflange now forms a tongue which extends into a notch in the first arcshaped flange. The actual holding means is then located between thenotch and the tongue. This may be an elastic band as before, but it maybe preferable that a spring loaded plunger be used instead.

The notch creates a casing for holding the spring and the plunger. Firstthe plunger and the spring are inserted in the casing, with the springfollowing around the shaft of the plunger. Then a center drilled screwis screwed into the casing to retain the spring and the plunger. Theshaft of the plunger can then be retracted through the center drilledscrew. The shaft is then attached to a holder in the tongue of thesecond arc shaped flange by fully retracting the plunger to make theattachment.

Thereafter the plunger will hold the two clips movably together. Toattach the flat sliding clip to the ear it is merely necessary to pullthe clips apart, fit them over the ears and then allow the retractingforce of the plunger and the holding means to pull the clips into acomfortable fit against the ears.

The third is a pneumatic clip using pneumatic pressure. An annularcasing having a central opening is fitted over the external ear to makecontact with the side of the head. This annular casing contains areservoir and an expandable annular tube connected to the reservoir andto the gas or mixture of gases in the reservoir. The annular tube isattached along the inner circumference of the annular casing. When theannular casing is placed over and around the ears to fit snugly againstthe side of the head, and a plunger connected to the reservoir is usedto exhaust the reservoir the expandable tube expands to snugly andannularly enclose the external ear, thereby tightly fitting thepneumatic clip to the side of the head.

The fourth is a hydraulic clip using hydraulic pressure. An annularcasing having a central opening is fitted over the external ear to makecontact with the side of the head. This annular casing contains areservoir and an expandable annular tube connected to the reservoir andto the hydraulic liquid in the reservoir. The annular tube is annularlyattached to the inner circumference of the annular casing. When theannular casing is placed over and around the ears to fit snugly againstthe side of the head, and a plunger connected to the reservoir is usedto exhaust the reservoir, the expandable tube expands to snugly andannularly enclose the external ear, thereby tightly fitting thehydraulic clip to the side of the head. It may also be preferable thatthe hydraulic fluid of said hydraulic clip is glycerin.

The plunger will be the same for both the pneumatic and the hydraulicclip. The plunger may have a locking means which, after exhausting thereservoir, allows the plunger to fit smoothly into the surface of theannular casing and which prevents it from rising above this surfaceuntil it is unlocked. The locking means may be a sliding latch which isrecessed into a latch casing in the plunger frame. The sliding latch maybe spring loaded and have an upwardly rounded tip that, upon contactwith the annular casing will smoothly ride back on its upwardly roundedtip to allow the plunger to be locked in place when the sliding latch isdepressed sufficiently to line up with the latch hole in the annularcasing. The top of the latch casing will have a sliding latch groove cutinto it, thereby allowing the latch button to be used to retract thesliding latch and unlock and remove the plunger from the reservoir.

Alternatively the plunger may simply have a friction or ratchet typelock, The plunger casing containing the plunger will make strongfrictional contact with the plunger so that the frictional force ishigher than the force exerted by the fluid on the plunger during normaloperation. After being moved into position the plunger will thereforeremain in that position until it is moved to a different position. Orthe plunger will have a series of small nubs which correspond toindentations in the plunger casing. When the nubs and the indentationsare lined up in a certain position they will then remain in thatposition until the plunger is moved again, manually.

When the plunger is removed from the reservoir fluid may return to thereservoir and easily allow the annular casing to be removed from theear.

It may therefore be preferable that according to one of its aspects theinvention further comprises; A latching means for proximally attachingdevices to the ear wherein;

said flat sliding clip is comprised of a first arc shaped flange havinga curvature corresponding to the shape of the anterior portion of theexternal ear and a second arc shaped flange having a curvaturecorresponding to the shape of the posterior portion of the external ear,so that when said flat sliding clip is attached to the ear by wedgingsaid second arc shaped flange in behind the posterior portion of theexternal ear, said first arc shaped flange may be movably fitted againstthe anterior portion of the external ear,so that in operation said second arc shaped flange is fitted into saidfirst arc shaped flange by inserting a tongue protruding from saidsecond arc shaped flange into a notch in said first arc shaped flange,so that said first arc shaped flange and said second arc shaped flangeare held together by elastic tension, whereby said flat sliding clip isclasped between the external ear and the side of the head,so that said flat sliding clip comprises a means for proximallyattaching devices to the ear, and; wherein said jointed clip iscomprised of a first part shaped to fit the curvature of the anteriorhalf of the external ear, and a second part shaped to fit the curvatureof the posterior half of the external ear, and;wherein said second part of said jointed clip is attached by a hinge toa pivot mounted in the distal end of said first part;the distal end of the second part further having a tongue for latchinginto a tongue groove located on the proximal end of said first part,so that when said jointed clip is attached to the external ear bywedging said first part against the anterior portion of the externalear, said second part may be movably fitted through rotation about saidhinge in behind the posterior portion of the external ear,so that in operation said second part is fitted laterally over saidfirst part and locked in place by said tongue groove, and;said jointed clip is clasped between the external ear and the side ofthe head, so that said jointed clip comprises a means for proximallyattaching elements to the ear, and;wherein said pneumatic clip is comprised of an annular casing having acentral opening, said annular casing further comprising a holding grooveand a holding case fashioned to follow the circumference of said centralopening, and;said annular casing further comprising an annular expandable pneumatictube and pneumatic reservoir, said annular expandable pneumatic tubeheld in said holding groove and said pneumatic reservoir held in saidholding case, and;said annular casing further comprising an adjustable plunger forapplying a variable pressure to said pneumatic reservoir, said plungerhaving a latch for holding said plunger in position during operation,so that when said plunger applies pressure to said pneumatic reservoirduring operation the hydraulic fluid in said pneumatic reservoir isexpelled from said pneumatic reservoir into said annular expandablepneumatic tube, thereby forcing said annular expandable pneumatic tubeto expand and clasp the pneumatic clip to the external ear and the sideof the head, and;when said plunger is retracted, the fluid in said annular expandablepneumatic tube is allowed to return to said pneumatic reservoir,so that by decreasing said variable pressure on said pneumatic reservoirthe external ear can be moved through said annular expandable pneumatictube and said central opening, and by increasing said variable pressureon said pneumatic reservoir, said pneumatic clip can be clasped to theexternal ear and the side of the head,whereby said pneumatic clip comprises a means for proximally attachingdevices to the ear, and;wherein said hydraulic clip is comprised of an annular casing having acentral opening, said annular casing further comprising a holding grooveand a holding case fashioned to follow the circumference of said centralopening, and;said annular casing further comprising an annular expandable hydraulictube and hydraulic reservoir, said annular expandable hydraulic tubeheld in said holding groove and said hydraulic reservoir held in saidholding case, and;said annular casing further comprising an adjustable plunger forapplying a variable pressure to said hydraulic reservoir, said plungerhaving a latch for holding said plunger in position during operation,so that when said plunger applies pressure to said hydraulic reservoirduring operation the hydraulic fluid in said hydraulic reservoir isexpelled from said hydraulic reservoir into said annular expandablehydraulic tube, thereby forcing said annular expandable hydraulic tubeto expand and clasp the hydraulic clip to the external ear and the sideof the head, and;when said plunger is retracted, the fluid in said annular expandablehydraulic tube is allowed to return to said hydraulic reservoir,so that by decreasing said variable pressure on said hydraulic reservoirthe external ear can be moved through said annular expandable hydraulictube and said central opening, and by increasing said variable pressureon said hydraulic reservoir, said hydraulic clip can be clasped to theexternal ear and the side of the headwhereby said hydraulic clip comprises a means for proximally attachingdevices to the ear, and;the lateral surface of said plurality of clips having a supportingmaterial for cushioning said clips against the ear lobe, so that whensaid plurality of clips is latched against the ear during operation, thesupporting material of said lateral surface of said plurality of clipspresses laterally against the external ear, and; the medial surface ofsaid plurality of clips having a wedge shaped layer of bracing materialapplied to it, the thicker part of said wedge shaped layer attached tothe posterior circumference of said second arc shaped flange or saidannular casing, the thinner part of said wedge shaped layer comprising afrontal pad for sealing and fitting the anterior circumference of saidfirst arc shaped flange or said annular casing against the head andjawbone, and;

said bracing material further having a cushioned lip contour forcomplementing the shape of the head and neck during operation, such thatsaid cushioned lip contour curves the bracing material of said latchingmeans laterally away from the head where it touches the jaw bone and theside arch of the skull, and said cushioned lip contour curves thebracing material of said latching means medially towards the head andneck where it touches the human body surface beneath the jaw bone andthe external ear,

so that when said latching means is locked in place between the externalear and the side of the head the posterior portion of said latchingmeans is moved laterally by said wedge shaped layer of bracing material,thereby pressing and sealing the frontal pad against the head andjawbone, so that said latching means comprises a means for proximallyattaching devices to the ear.

As shown in FIG. 31, another particular of the invention is incombination with a head phone set having speakers (562, 563) attached toa fitting means (564) for placing said speakers against the ears and aconnecting means (566) for connecting said speakers to a playback unit,the improvement comprising;

A pair of sound baffling cups (568, 570) for fully enclosing the earsbetween said sound baffling cups and the head and neck during operation,said sound baffling cups inserted between said speakers and said fittingmeans, said speakers attached to the interior of said sound bafflingcups, so that the ambient noise reaching the ears during operation issubstantially reduced, thereby improving the audibility and perceivedrendition of the sound emanating from said speakers, and;

A cushioned lip contour (572, 574) for complimenting the shape of thehead and neck during operation, said cushioned lip contour applied tothe lips (576, 578) of said sound baffling cups such that said cushionedlip contour curves the lips of said sound baffling cups laterally awayfrom the head where it touches the jaw bone and the side arch of theskull, and said cushioned lip contour curves the lips of said soundbaffling cups medially towards the head and neck where it touches thehuman body surface beneath the jaw bone and behind the inferior externalear, so that the comfort, fit, and sound baffling qualities of saidsound baffling cups are substantially improved by said cushioned lipcontour.

As shown in FIG. 32, in another particular of the invention a first partof the connecting means (581, 582) which connects to the far speaker(580) is carried along said fitting means (583) and gathered together toform a bundle (584) with a second part (585, 586) of the connectingmeans which connects to the near speaker (587), both the first andsecond part of said connecting means extending from said bundle toconnect with the connecting means connection (588), so that when saidconnecting means connection is connected to the playback unit connector,a single path is followed by said connecting means from the speakers ofsaid head phone set to said playback unit.

Rather than carrying the first part of the connecting means along thefitting means by means of a wiring arrangement, it may be preferable touse the fitting means as an insulating substrate for conductive strips(589, 590, 591, 592), which carry the first part of the connecting meansalong the fitting means. In FIG. 27, the conductive strips (589, 591)running along the top of the fitting means are electronically connectedby contacts (593, 594) which are attached to the restraining bands ofthe fitting means. The conductive strips (590, 592) running along theside of the fitting means are in continuous contact with each other.These factors ensure that the fitting means may function reliably as asubstrate for the conductive strips of the connecting means.

Furthermore, as shown in FIG. 34, by using a fitting means comprised ofhollow tubular segments, it is possible to pass the connecting meansfrom one speaker to the other through the hollow tubular segments of thefitting means. As illustrated, the middle tube (597) functions as aguide for the first tube (598) and the second tube (599). Thiseliminates unsightly wiring arrangement and also creates greatercompactness of engineering. It is therefore preferable that said fittingmeans is comprised of elastic hollow tubular segments (597, 598, 599)fashioned to allow a smaller tubular segment (598, 599) to slide fixedlywithin a larger tubular segment (597), said hollow tubular segmentshaving a restraining means (600, 601, 602, 603) to prevent separation,and;

wherein the length of the arc described by said fitting means is set bysliding said smaller tubular segment to a preferred position within saidlarger tubular segment, so that the length of the arc may be reducedsufficiently to allow said elastic arc shaped tubes to be worn behindthe neck, and;

the first part (604, 605) of the connecting means which connects to thefar speaker (606) is carried through said tubes and gathered together toform a bundle (607) with the second part (608, 609) of the connectingmeans which connects to the near speaker (610), thereby improving theappearance, comfort and utility of said device. This embodiment may alsobe fashioned from a larger elastic arc shaped tube and a smaller elasticarc shaped tube. And the retraining means of this embodiment is formedby means of the interlocking tube ends (600, 601) and (602, 603). Thetight frictional fit of the tubes allows the size of the arc to beadjusted by the frictional feed.

Because the lips of the sound baffling cups form a more stablefoundation than the loosely fitting padded speakers or plug-in speakersof some previous head phone sets, it is possible to apply more elastictension to head phone sets using sound baffling cups. When the elastictension is increased by a suitable amount, the arc shaped fitting meansused in some previous devices may be worn in an arc behind the neck. Itis therefore preferable that said fitting means is comprised of twoslidably connected elastic arc shaped bands to which the sound bafflingcups are attached, and;

wherein the improvement comprises an increase in the tension applied bysaid arc shaped band to the sound baffling cups, so that when said arcshaped bands are shortened so as to be worn behind the neck, saidincrease in the tension allows said sound baffling cups to maintain asnug fit against the ears, thereby improving the comfort and utility ofsaid device.

The advantage of placing the fitting means in this fashion is that it isless obtrusive and that headgear may be worn. This embodiment may beimproved further by providing arc shaped bands that are grooved. Thetubular grooves serve as a guide for the connecting means and allow itto be passed more easily from the far speaker to the near speaker.Therefore as shown in FIG. 35, according to another particular of theinvention it is preferable that said elastic arc shaped bands aregrooved, and;

a first part (612, 613) of the connecting means which connects to thefar speaker (614) is carried through said elastic arc shaped bands (616,617) and gathered together to form a bundle (618) with a second part(620, 621) of the connecting means which connects to the near speaker(622), both the first and second parts of said connecting meansextending from said bundle to connect with the connecting meansconnection (624), so that when said connecting means connection isconnected to the playback unit connector, a single path is followed bysaid connecting means from the speakers of said head phone set to saidplayback unit, thereby improving the appearance, comfort and utility ofsaid device.

The connecting means may be the usual wiring arrangement shown in manyprevious devices. But it may also be comprised of fiber optic cable orit could be fashioned from wire-less or infrared radiation devices. Thefiber optic cable confers a better quality to the connecting means,whereas the wire-less or infrared radiation eliminate the wiringarrangement thereby making the connecting means less obtrusive.

What is claimed is:
 1. A latching means for attaching an elementproximally to the ear, said latching means fully encircling the earcanal of the external ear during operation, said latching means selectedfrom the group consisting of a jointed clip, a flat sliding clip, apneumatic clip, and a hydraulic clip; wherein said jointed clipcomprises a first part shaped to fit the curvature of the anterior halfof the external ear, and a second part shaped to fit the curvature ofthe posterior half of the external ear, and; wherein said second part ofsaid jointed clip is attached by a hinge to a pivot mounted in thedistal end of said first part; the distal end of the second part furtherhaving a tongue for latching into a tongue groove located on theproximal end of said first part, so that when said jointed clip isattached to the external ear by wedging said first part against theanterior portion of the external ear, said second part may be movablyfitted through rotation about said pivot in behind the posterior portionof the external ear, so that in operation said second part is fittedlaterally over said first part and locked in place by said tonguegroove, and; said jointed clip is clasped between the external ear andthe side of the head, so that said jointed clip comprises a means forproximally attaching elements to the ear, and; wherein said flat slidingclip comprises a first arc shaped flange having a curvaturecorresponding to the shape of the anterior portion of the external earand a second arc shaped flange having a curvature corresponding to theshape of the posterior portion of the external ear, so that when saidflat sliding clip is attached to the ear by wedging said second arcshaped flange in behind the posterior portion of the external ear, saidfirst arc shaped flange may be movably fitted against the anteriorportion of the external ear, so that in operation said second arc shapedflange is fitted into said first arc shaped flange by inserting a tongueprotruding from said second arc shaped flange into a notch in said firstarc shaped flange, so that said first arc shaped flange and said secondarc shaped flange are held together by elastic tension, whereby saidflat sliding clip is clasped between the external ear and the side ofthe head, so that said flat sliding clip comprises a means forproximally attaching elements to the ear, and; wherein said pneumaticclip comprises an annular casing having a central opening, said annularcasing further comprising a holding groove and a holding case fashionedto follow the circumference of said central opening, and; said annularcasing further comprising an annular expandable pneumatic tube andpneumatic reservoir, said annular expandable pneumatic tube held in saidholding groove and said pneumatic reservoir held in said holding case,and; said annular casing further comprising an adjustable plunger forapplying a variable pressure to said pneumatic reservoir, said plungerhaving a latch for holding said plunger in position during operation, sothat when said plunger applies pressure to said pneumatic reservoirduring operation the hydraulic fluid in said pneumatic reservoir isexpelled from said pneumatic reservoir into said annular expandablepneumatic tube, thereby forcing said annular expandable pneumatic tubeto expand and clasp the pneumatic clip to the external ear and the sideof the head, and; when said plunger is retracted, the fluid in saidannular expandable pneumatic tube is allowed to return to said pneumaticreservoir, so that by decreasing said variable pressure on saidpneumatic reservoir the external ear can be moved through said annularexpandable pneumatic tube and said central opening, and by increasingsaid variable pressure on said pneumatic reservoir, said pneumatic clipcan be clasped to the external ear and the side of the head, wherebysaid pneumatic clip comprises a means for proximally attaching elementsto the ear, and; wherein said hydraulic clip comprises an annular casinghaving a central opening, said annular casing further comprising aholding groove and a holding case fashioned to follow the circumferenceof said central opening, and; said annular casing further comprising anannular expandable hydraulic tube and hydraulic reservoir, said annularexpandable hydraulic tube held in said holding groove and said hydraulicreservoir held in said holding case, and; said annular casing furthercomprising an adjustable plunger for applying a variable pressure tosaid hydraulic reservoir, said plunger having a latch for holding saidplunger in position during operation, so that when said plunger appliespressure to said hydraulic reservoir during operation the hydraulicfluid in said hydraulic reservoir is expelled from said hydraulicreservoir into said annular expandable hydraulic tube, thereby forcingsaid annular expandable hydraulic tube to expand and clasp the hydraulicclip to the external ear and the side of the head, and; when saidplunger is retracted, the fluid in said annular expandable hydraulictube is allowed to return to said hydraulic reservoir, so that bydecreasing said variable pressure on said hydraulic reservoir theexternal ear can be moved through said annular expandable hydraulic tubeand said central opening, and by increasing said variable pressure onsaid hydraulic reservoir, said hydraulic clip can be clasped to theexternal ear and the side of the head, whereby said hydraulic clipcomprises a means for proximally attaching elements to the ear, and;wherein a lateral surface of said latching means has a supportingmaterial for cushioning said clips against the ear lobe, so that whensaid latching means is latched against the ear during operation, thesupporting material of said lateral surface of said latching meanspresses laterally against the external ear, and; wherein a medialsurface of said latching means has a wedge shaped layer of bracingmaterial applied to it, the thicker part of said wedge shaped layerattached to the posterior circumference of said second art or saidsecond arc shared flange or said annular casing, the thinner part ofsaid wedge shaped layer comprising a frontal pad for sealing and fittingthe anterior circumference of said first part or said first arc shapedflange or said annular casing against the head and jawbone, and; saidbracing material further having a cushioned lip contour forcomplementing the shape of the head and neck during operation, so thatsaid cushioned lip contour curves the bracing material of said latchingmeans laterally away from the head where it touches the jaw bone and theside arch of the skull, and said cushioned lip contour curves thebracing material of said latching means medially towards the head andneck where it touches the human body surface beneath the jaw bone andthe external ear, so that when said latching means is locked in placebetween the external ear and the side of the head the posterior portionof said latching means is moved laterally by said wedge shaped layer ofbracing material, thereby pressing and sealing the frontal pad againstthe head and jawbone, so that said latching means comprises a means forproximally attaching elements to the ear.
 2. The latching means of claim1 further comprising a transduction circuit for regulating the soundtransmitted through a solid, said transduction circuit selected from thegroup consisting of a noise canceling transduction circuit, a soundcanceling transduction circuit, a modulation transduction circuit, amodulated noise canceling transduction circuit, and a modulated soundcanceling transduction circuit.
 3. The latching means of claim 1 whereinthe flat sliding clip comprises a spring loaded plunger that providessaid elastic tension for holding said second arc shaped flange againstsaid first arc shaped flange.
 4. The latching means of claim 1comprising said pneumatic clip or hydraulic clip, and wherein saidadjustable plunger has a friction feed, or a ratchet locking mechanism,or nubs for holding said adjustable plunger in position.
 5. The latchingmeans of claim 1 further comprising contact eyes or contact facets,whereby devices are attached to said latching means.
 6. The latchingmeans of claim 5, wherein said devices are selected from the groupconsisting of a sound baffling cup, a sound baffling cup comprising avacuum, a speaker, a microphone, and a sound baffling cup comprising aspeaker.